6.5: tcp patches #3
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Adds a lot of overhead. Signed-off-by: Kazuki Hashimoto <kazukih0205@gmail.com>
…tency `TCP_NODELAY` will disable Nagle's algorithm, which basically collects small outgoing packets to send all at once. Thus `TCP_NODELAY` will send the data whenever it is available without waiting for any period to collect packets. It will basically optimize network video games and applications using chatty protocols (source: ExtraHop[1], RedHat[2]) [1]: https://www.extrahop.com/company/blog/2016/tcp-nodelay-nagle-quickack-best-practices/#:~:text=The%20TCP_NODELAY%20socket%20option%20allows,buffer%2C%20whatever%20the%20packet%20size. [2]: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux_for_real_time/7/html/tuning_guide/tcp_nodelay_and_small_buffer_writes Signed-off-by: Panchajanya1999 <panchajanya@azure-dev.live> [Rasenkai: forward-port to 5.4] Signed-off-by: Rasenkai <rasenkai99@gmail.com> Change-Id: I2518d04969975c69c61d5e0acab7295702190b0d
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Hou Tao says: ==================== Fix the unmatched unit_size of bpf_mem_cache From: Hou Tao <houtao1@huawei.com> Hi, The patchset aims to fix the reported warning [0] when the unit_size of bpf_mem_cache is mismatched with the object size of underly slab-cache. Patch #1 fixes the warning by adjusting size_index according to the value of KMALLOC_MIN_SIZE, so bpf_mem_cache with unit_size which is smaller than KMALLOC_MIN_SIZE or is not aligned with KMALLOC_MIN_SIZE will be redirected to bpf_mem_cache with bigger unit_size. Patch #2 doesn't do prefill for these redirected bpf_mem_cache to save memory. Patch #3 adds further error check in bpf_mem_alloc_init() to ensure the unit_size and object_size are always matched and to prevent potential issues due to the mismatch. Please see individual patches for more details. And comments are always welcome. [0]: https://lore.kernel.org/bpf/87jztjmmy4.fsf@all.your.base.are.belong.to.us ==================== Link: https://lore.kernel.org/r/20230908133923.2675053-1-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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macb_set_tx_clk() is called under a spinlock but itself calls clk_set_rate()
which can sleep. This results in:
| BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
| pps pps1: new PPS source ptp1
| in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 40, name: kworker/u4:3
| preempt_count: 1, expected: 0
| RCU nest depth: 0, expected: 0
| 4 locks held by kworker/u4:3/40:
| #0: ffff000003409148
| macb ff0c0000.ethernet: gem-ptp-timer ptp clock registered.
| ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x14c/0x51c
| #1: ffff8000833cbdd8 ((work_completion)(&pl->resolve)){+.+.}-{0:0}, at: process_one_work+0x14c/0x51c
| #2: ffff000004f01578 (&pl->state_mutex){+.+.}-{4:4}, at: phylink_resolve+0x44/0x4e8
| #3: ffff000004f06f50 (&bp->lock){....}-{3:3}, at: macb_mac_link_up+0x40/0x2ac
| irq event stamp: 113998
| hardirqs last enabled at (113997): [<ffff800080e8503c>] _raw_spin_unlock_irq+0x30/0x64
| hardirqs last disabled at (113998): [<ffff800080e84478>] _raw_spin_lock_irqsave+0xac/0xc8
| softirqs last enabled at (113608): [<ffff800080010630>] __do_softirq+0x430/0x4e4
| softirqs last disabled at (113597): [<ffff80008001614c>] ____do_softirq+0x10/0x1c
| CPU: 0 PID: 40 Comm: kworker/u4:3 Not tainted 6.5.0-11717-g9355ce8b2f50-dirty torvalds#368
| Hardware name: ... ZynqMP ... (DT)
| Workqueue: events_power_efficient phylink_resolve
| Call trace:
| dump_backtrace+0x98/0xf0
| show_stack+0x18/0x24
| dump_stack_lvl+0x60/0xac
| dump_stack+0x18/0x24
| __might_resched+0x144/0x24c
| __might_sleep+0x48/0x98
| __mutex_lock+0x58/0x7b0
| mutex_lock_nested+0x24/0x30
| clk_prepare_lock+0x4c/0xa8
| clk_set_rate+0x24/0x8c
| macb_mac_link_up+0x25c/0x2ac
| phylink_resolve+0x178/0x4e8
| process_one_work+0x1ec/0x51c
| worker_thread+0x1ec/0x3e4
| kthread+0x120/0x124
| ret_from_fork+0x10/0x20
The obvious fix is to move the call to macb_set_tx_clk() out of the
protected area. This seems safe as rx and tx are both disabled anyway at
this point.
It is however not entirely clear what the spinlock shall protect. It
could be the read-modify-write access to the NCFGR register, but this
is accessed in macb_set_rx_mode() and macb_set_rxcsum_feature() as well
without holding the spinlock. It could also be the register accesses
done in mog_init_rings() or macb_init_buffers(), but again these
functions are called without holding the spinlock in macb_hresp_error_task().
The locking seems fishy in this driver and it might deserve another look
before this patch is applied.
Fixes: 633e98a ("net: macb: use resolved link config in mac_link_up()")
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://lore.kernel.org/r/20230908112913.1701766-1-s.hauer@pengutronix.de
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Fix an error detected by memory sanitizer:
```
==4033==WARNING: MemorySanitizer: use-of-uninitialized-value
#0 0x55fb0fbedfc7 in read_alias_info tools/perf/util/pmu.c:457:6
#1 0x55fb0fbea339 in check_info_data tools/perf/util/pmu.c:1434:2
#2 0x55fb0fbea339 in perf_pmu__check_alias tools/perf/util/pmu.c:1504:9
#3 0x55fb0fbdca85 in parse_events_add_pmu tools/perf/util/parse-events.c:1429:32
#4 0x55fb0f965230 in parse_events_parse tools/perf/util/parse-events.y:299:6
#5 0x55fb0fbdf6b2 in parse_events__scanner tools/perf/util/parse-events.c:1822:8
torvalds#6 0x55fb0fbdf8c1 in __parse_events tools/perf/util/parse-events.c:2094:8
torvalds#7 0x55fb0fa8ffa9 in parse_events tools/perf/util/parse-events.h:41:9
torvalds#8 0x55fb0fa8ffa9 in test_event tools/perf/tests/parse-events.c:2393:8
torvalds#9 0x55fb0fa8f458 in test__pmu_events tools/perf/tests/parse-events.c:2551:15
torvalds#10 0x55fb0fa6d93f in run_test tools/perf/tests/builtin-test.c:242:9
torvalds#11 0x55fb0fa6d93f in test_and_print tools/perf/tests/builtin-test.c:271:8
torvalds#12 0x55fb0fa6d082 in __cmd_test tools/perf/tests/builtin-test.c:442:5
torvalds#13 0x55fb0fa6d082 in cmd_test tools/perf/tests/builtin-test.c:564:9
torvalds#14 0x55fb0f942720 in run_builtin tools/perf/perf.c:322:11
torvalds#15 0x55fb0f942486 in handle_internal_command tools/perf/perf.c:375:8
torvalds#16 0x55fb0f941dab in run_argv tools/perf/perf.c:419:2
torvalds#17 0x55fb0f941dab in main tools/perf/perf.c:535:3
```
Fixes: 7b723db ("perf pmu: Be lazy about loading event info files from sysfs")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@arm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20230914022425.1489035-1-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Syzkaller reported a sleep in atomic context bug relating to the HASHCHK handler logic: BUG: sleeping function called from invalid context at arch/powerpc/kernel/traps.c:1518 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 25040, name: syz-executor preempt_count: 0, expected: 0 RCU nest depth: 0, expected: 0 no locks held by syz-executor/25040. irq event stamp: 34 hardirqs last enabled at (33): [<c000000000048b38>] prep_irq_for_enabled_exit arch/powerpc/kernel/interrupt.c:56 [inline] hardirqs last enabled at (33): [<c000000000048b38>] interrupt_exit_user_prepare_main+0x148/0x600 arch/powerpc/kernel/interrupt.c:230 hardirqs last disabled at (34): [<c00000000003e6a4>] interrupt_enter_prepare+0x144/0x4f0 arch/powerpc/include/asm/interrupt.h:176 softirqs last enabled at (0): [<c000000000281954>] copy_process+0x16e4/0x4750 kernel/fork.c:2436 softirqs last disabled at (0): [<0000000000000000>] 0x0 CPU: 15 PID: 25040 Comm: syz-executor Not tainted 6.5.0-rc5-00001-g3ccdff6bb06d #3 Hardware name: IBM,9105-22A POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1040.00 (NL1040_021) hv:phyp pSeries Call Trace: [c0000000a8247ce0] [c00000000032b0e4] __might_resched+0x3b4/0x400 kernel/sched/core.c:10189 [c0000000a8247d80] [c0000000008c7dc8] __might_fault+0xa8/0x170 mm/memory.c:5853 [c0000000a8247dc0] [c00000000004160c] do_program_check+0x32c/0xb20 arch/powerpc/kernel/traps.c:1518 [c0000000a8247e50] [c000000000009b2c] program_check_common_virt+0x3bc/0x3c0 To determine if a trap was caused by a HASHCHK instruction, we inspect the user instruction that triggered the trap. However this may sleep if the page needs to be faulted in (get_user_instr() reaches __get_user(), which calls might_fault() and triggers the bug message). Move the HASHCHK handler logic to after we allow IRQs, which is fine because we are only interested in HASHCHK if it's a user space trap. Fixes: 5bcba4e ("powerpc/dexcr: Handle hashchk exception") Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230915034604.45393-1-bgray@linux.ibm.com
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Sebastian Andrzej Siewior says: ==================== net: hsr: Properly parse HSRv1 supervisor frames. this is a follow-up to https://lore.kernel.org/all/20230825153111.228768-1-lukma@denx.de/ replacing https://lore.kernel.org/all/20230914124731.1654059-1-lukma@denx.de/ by grabing/ adding tags and reposting with a commit message plus a missing __packed to a struct (#2) plus extending the testsuite to sover HSRv1 which is what broke here (#3-#5). HSRv0 is (was) not affected. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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[ Upstream commit c3f4309 ] Syzkaller reported a sleep in atomic context bug relating to the HASHCHK handler logic: BUG: sleeping function called from invalid context at arch/powerpc/kernel/traps.c:1518 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 25040, name: syz-executor preempt_count: 0, expected: 0 RCU nest depth: 0, expected: 0 no locks held by syz-executor/25040. irq event stamp: 34 hardirqs last enabled at (33): [<c000000000048b38>] prep_irq_for_enabled_exit arch/powerpc/kernel/interrupt.c:56 [inline] hardirqs last enabled at (33): [<c000000000048b38>] interrupt_exit_user_prepare_main+0x148/0x600 arch/powerpc/kernel/interrupt.c:230 hardirqs last disabled at (34): [<c00000000003e6a4>] interrupt_enter_prepare+0x144/0x4f0 arch/powerpc/include/asm/interrupt.h:176 softirqs last enabled at (0): [<c000000000281954>] copy_process+0x16e4/0x4750 kernel/fork.c:2436 softirqs last disabled at (0): [<0000000000000000>] 0x0 CPU: 15 PID: 25040 Comm: syz-executor Not tainted 6.5.0-rc5-00001-g3ccdff6bb06d #3 Hardware name: IBM,9105-22A POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1040.00 (NL1040_021) hv:phyp pSeries Call Trace: [c0000000a8247ce0] [c00000000032b0e4] __might_resched+0x3b4/0x400 kernel/sched/core.c:10189 [c0000000a8247d80] [c0000000008c7dc8] __might_fault+0xa8/0x170 mm/memory.c:5853 [c0000000a8247dc0] [c00000000004160c] do_program_check+0x32c/0xb20 arch/powerpc/kernel/traps.c:1518 [c0000000a8247e50] [c000000000009b2c] program_check_common_virt+0x3bc/0x3c0 To determine if a trap was caused by a HASHCHK instruction, we inspect the user instruction that triggered the trap. However this may sleep if the page needs to be faulted in (get_user_instr() reaches __get_user(), which calls might_fault() and triggers the bug message). Move the HASHCHK handler logic to after we allow IRQs, which is fine because we are only interested in HASHCHK if it's a user space trap. Fixes: 5bcba4e ("powerpc/dexcr: Handle hashchk exception") Signed-off-by: Benjamin Gray <bgray@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230915034604.45393-1-bgray@linux.ibm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
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Fix the deadlock by refactoring the MR cache cleanup flow to flush the workqueue without holding the rb_lock. This adds a race between cache cleanup and creation of new entries which we solve by denied creation of new entries after cache cleanup started. Lockdep: WARNING: possible circular locking dependency detected [ 2785.326074 ] 6.2.0-rc6_for_upstream_debug_2023_01_31_14_02 #1 Not tainted [ 2785.339778 ] ------------------------------------------------------ [ 2785.340848 ] devlink/53872 is trying to acquire lock: [ 2785.341701 ] ffff888124f8c0c8 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0xc8/0x900 [ 2785.343403 ] [ 2785.343403 ] but task is already holding lock: [ 2785.344464 ] ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib] [ 2785.346273 ] [ 2785.346273 ] which lock already depends on the new lock. [ 2785.346273 ] [ 2785.347720 ] [ 2785.347720 ] the existing dependency chain (in reverse order) is: [ 2785.349003 ] [ 2785.349003 ] -> #1 (&dev->cache.rb_lock){+.+.}-{3:3}: [ 2785.350160 ] __mutex_lock+0x14c/0x15c0 [ 2785.350962 ] delayed_cache_work_func+0x2d1/0x610 [mlx5_ib] [ 2785.352044 ] process_one_work+0x7c2/0x1310 [ 2785.352879 ] worker_thread+0x59d/0xec0 [ 2785.353636 ] kthread+0x28f/0x330 [ 2785.354370 ] ret_from_fork+0x1f/0x30 [ 2785.355135 ] [ 2785.355135 ] -> #0 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}: [ 2785.356515 ] __lock_acquire+0x2d8a/0x5fe0 [ 2785.357349 ] lock_acquire+0x1c1/0x540 [ 2785.358121 ] __flush_work+0xe8/0x900 [ 2785.358852 ] __cancel_work_timer+0x2c7/0x3f0 [ 2785.359711 ] mlx5_mkey_cache_cleanup+0xfb/0x250 [mlx5_ib] [ 2785.360781 ] mlx5_ib_stage_pre_ib_reg_umr_cleanup+0x16/0x30 [mlx5_ib] [ 2785.361969 ] __mlx5_ib_remove+0x68/0x120 [mlx5_ib] [ 2785.362960 ] mlx5r_remove+0x63/0x80 [mlx5_ib] [ 2785.363870 ] auxiliary_bus_remove+0x52/0x70 [ 2785.364715 ] device_release_driver_internal+0x3c1/0x600 [ 2785.365695 ] bus_remove_device+0x2a5/0x560 [ 2785.366525 ] device_del+0x492/0xb80 [ 2785.367276 ] mlx5_detach_device+0x1a9/0x360 [mlx5_core] [ 2785.368615 ] mlx5_unload_one_devl_locked+0x5a/0x110 [mlx5_core] [ 2785.369934 ] mlx5_devlink_reload_down+0x292/0x580 [mlx5_core] [ 2785.371292 ] devlink_reload+0x439/0x590 [ 2785.372075 ] devlink_nl_cmd_reload+0xaef/0xff0 [ 2785.372973 ] genl_family_rcv_msg_doit.isra.0+0x1bd/0x290 [ 2785.374011 ] genl_rcv_msg+0x3ca/0x6c0 [ 2785.374798 ] netlink_rcv_skb+0x12c/0x360 [ 2785.375612 ] genl_rcv+0x24/0x40 [ 2785.376295 ] netlink_unicast+0x438/0x710 [ 2785.377121 ] netlink_sendmsg+0x7a1/0xca0 [ 2785.377926 ] sock_sendmsg+0xc5/0x190 [ 2785.378668 ] __sys_sendto+0x1bc/0x290 [ 2785.379440 ] __x64_sys_sendto+0xdc/0x1b0 [ 2785.380255 ] do_syscall_64+0x3d/0x90 [ 2785.381031 ] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 2785.381967 ] [ 2785.381967 ] other info that might help us debug this: [ 2785.381967 ] [ 2785.383448 ] Possible unsafe locking scenario: [ 2785.383448 ] [ 2785.384544 ] CPU0 CPU1 [ 2785.385383 ] ---- ---- [ 2785.386193 ] lock(&dev->cache.rb_lock); [ 2785.386940 ] lock((work_completion)(&(&ent->dwork)->work)); [ 2785.388327 ] lock(&dev->cache.rb_lock); [ 2785.389425 ] lock((work_completion)(&(&ent->dwork)->work)); [ 2785.390414 ] [ 2785.390414 ] *** DEADLOCK *** [ 2785.390414 ] [ 2785.391579 ] 6 locks held by devlink/53872: [ 2785.392341 ] #0: ffffffff84c17a50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 [ 2785.393630 ] #1: ffff888142280218 (&devlink->lock_key){+.+.}-{3:3}, at: devlink_get_from_attrs_lock+0x12d/0x2d0 [ 2785.395324 ] #2: ffff8881422d3c38 (&dev->lock_key){+.+.}-{3:3}, at: mlx5_unload_one_devl_locked+0x4a/0x110 [mlx5_core] [ 2785.397322 ] #3: ffffffffa0e59068 (mlx5_intf_mutex){+.+.}-{3:3}, at: mlx5_detach_device+0x60/0x360 [mlx5_core] [ 2785.399231 ] #4: ffff88810e3cb0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x8d/0x600 [ 2785.400864 ] #5: ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib] Fixes: b958451 ("RDMA/mlx5: Change the cache structure to an RB-tree") Signed-off-by: Shay Drory <shayd@nvidia.com> Signed-off-by: Michael Guralnik <michaelgur@nvidia.com> Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
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The following call trace shows a deadlock issue due to recursive locking of mutex "device_mutex". First lock acquire is in target_for_each_device() and second in target_free_device(). PID: 148266 TASK: ffff8be21ffb5d00 CPU: 10 COMMAND: "iscsi_ttx" #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224 #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7 #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3 #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c torvalds#6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod] torvalds#7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod] torvalds#8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f torvalds#9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583 torvalds#10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod] torvalds#11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc torvalds#12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod] torvalds#13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod] torvalds#14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod] torvalds#15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod] torvalds#16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07 torvalds#17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod] torvalds#18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod] torvalds#19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080 torvalds#20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364 Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion") Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com Reviewed-by: Mike Christie <michael.christie@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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[ Upstream commit a154f5f ] The following call trace shows a deadlock issue due to recursive locking of mutex "device_mutex". First lock acquire is in target_for_each_device() and second in target_free_device(). PID: 148266 TASK: ffff8be21ffb5d00 CPU: 10 COMMAND: "iscsi_ttx" #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224 #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7 #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3 #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c torvalds#6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod] torvalds#7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod] torvalds#8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f torvalds#9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583 torvalds#10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod] torvalds#11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc torvalds#12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod] torvalds#13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod] torvalds#14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod] torvalds#15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod] torvalds#16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07 torvalds#17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod] torvalds#18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod] torvalds#19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080 torvalds#20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364 Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion") Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com Reviewed-by: Mike Christie <michael.christie@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 374012b upstream. Fix the deadlock by refactoring the MR cache cleanup flow to flush the workqueue without holding the rb_lock. This adds a race between cache cleanup and creation of new entries which we solve by denied creation of new entries after cache cleanup started. Lockdep: WARNING: possible circular locking dependency detected [ 2785.326074 ] 6.2.0-rc6_for_upstream_debug_2023_01_31_14_02 #1 Not tainted [ 2785.339778 ] ------------------------------------------------------ [ 2785.340848 ] devlink/53872 is trying to acquire lock: [ 2785.341701 ] ffff888124f8c0c8 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0xc8/0x900 [ 2785.343403 ] [ 2785.343403 ] but task is already holding lock: [ 2785.344464 ] ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib] [ 2785.346273 ] [ 2785.346273 ] which lock already depends on the new lock. [ 2785.346273 ] [ 2785.347720 ] [ 2785.347720 ] the existing dependency chain (in reverse order) is: [ 2785.349003 ] [ 2785.349003 ] -> #1 (&dev->cache.rb_lock){+.+.}-{3:3}: [ 2785.350160 ] __mutex_lock+0x14c/0x15c0 [ 2785.350962 ] delayed_cache_work_func+0x2d1/0x610 [mlx5_ib] [ 2785.352044 ] process_one_work+0x7c2/0x1310 [ 2785.352879 ] worker_thread+0x59d/0xec0 [ 2785.353636 ] kthread+0x28f/0x330 [ 2785.354370 ] ret_from_fork+0x1f/0x30 [ 2785.355135 ] [ 2785.355135 ] -> #0 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}: [ 2785.356515 ] __lock_acquire+0x2d8a/0x5fe0 [ 2785.357349 ] lock_acquire+0x1c1/0x540 [ 2785.358121 ] __flush_work+0xe8/0x900 [ 2785.358852 ] __cancel_work_timer+0x2c7/0x3f0 [ 2785.359711 ] mlx5_mkey_cache_cleanup+0xfb/0x250 [mlx5_ib] [ 2785.360781 ] mlx5_ib_stage_pre_ib_reg_umr_cleanup+0x16/0x30 [mlx5_ib] [ 2785.361969 ] __mlx5_ib_remove+0x68/0x120 [mlx5_ib] [ 2785.362960 ] mlx5r_remove+0x63/0x80 [mlx5_ib] [ 2785.363870 ] auxiliary_bus_remove+0x52/0x70 [ 2785.364715 ] device_release_driver_internal+0x3c1/0x600 [ 2785.365695 ] bus_remove_device+0x2a5/0x560 [ 2785.366525 ] device_del+0x492/0xb80 [ 2785.367276 ] mlx5_detach_device+0x1a9/0x360 [mlx5_core] [ 2785.368615 ] mlx5_unload_one_devl_locked+0x5a/0x110 [mlx5_core] [ 2785.369934 ] mlx5_devlink_reload_down+0x292/0x580 [mlx5_core] [ 2785.371292 ] devlink_reload+0x439/0x590 [ 2785.372075 ] devlink_nl_cmd_reload+0xaef/0xff0 [ 2785.372973 ] genl_family_rcv_msg_doit.isra.0+0x1bd/0x290 [ 2785.374011 ] genl_rcv_msg+0x3ca/0x6c0 [ 2785.374798 ] netlink_rcv_skb+0x12c/0x360 [ 2785.375612 ] genl_rcv+0x24/0x40 [ 2785.376295 ] netlink_unicast+0x438/0x710 [ 2785.377121 ] netlink_sendmsg+0x7a1/0xca0 [ 2785.377926 ] sock_sendmsg+0xc5/0x190 [ 2785.378668 ] __sys_sendto+0x1bc/0x290 [ 2785.379440 ] __x64_sys_sendto+0xdc/0x1b0 [ 2785.380255 ] do_syscall_64+0x3d/0x90 [ 2785.381031 ] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 2785.381967 ] [ 2785.381967 ] other info that might help us debug this: [ 2785.381967 ] [ 2785.383448 ] Possible unsafe locking scenario: [ 2785.383448 ] [ 2785.384544 ] CPU0 CPU1 [ 2785.385383 ] ---- ---- [ 2785.386193 ] lock(&dev->cache.rb_lock); [ 2785.386940 ] lock((work_completion)(&(&ent->dwork)->work)); [ 2785.388327 ] lock(&dev->cache.rb_lock); [ 2785.389425 ] lock((work_completion)(&(&ent->dwork)->work)); [ 2785.390414 ] [ 2785.390414 ] *** DEADLOCK *** [ 2785.390414 ] [ 2785.391579 ] 6 locks held by devlink/53872: [ 2785.392341 ] #0: ffffffff84c17a50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 [ 2785.393630 ] #1: ffff888142280218 (&devlink->lock_key){+.+.}-{3:3}, at: devlink_get_from_attrs_lock+0x12d/0x2d0 [ 2785.395324 ] #2: ffff8881422d3c38 (&dev->lock_key){+.+.}-{3:3}, at: mlx5_unload_one_devl_locked+0x4a/0x110 [mlx5_core] [ 2785.397322 ] #3: ffffffffa0e59068 (mlx5_intf_mutex){+.+.}-{3:3}, at: mlx5_detach_device+0x60/0x360 [mlx5_core] [ 2785.399231 ] #4: ffff88810e3cb0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x8d/0x600 [ 2785.400864 ] #5: ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib] Fixes: b958451 ("RDMA/mlx5: Change the cache structure to an RB-tree") Signed-off-by: Shay Drory <shayd@nvidia.com> Signed-off-by: Michael Guralnik <michaelgur@nvidia.com> Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit a84fbf2 ] Generating metrics llc_code_read_mpi_demand_plus_prefetch, llc_data_read_mpi_demand_plus_prefetch, llc_miss_local_memory_bandwidth_read, llc_miss_local_memory_bandwidth_write, nllc_miss_remote_memory_bandwidth_read, memory_bandwidth_read, memory_bandwidth_write, uncore_frequency, upi_data_transmit_bw, C2_Pkg_Residency, C3_Core_Residency, C3_Pkg_Residency, C6_Core_Residency, C6_Pkg_Residency, C7_Core_Residency, C7_Pkg_Residency, UNCORE_FREQ and tma_info_system_socket_clks would trigger an address sanitizer heap-buffer-overflows on a SkylakeX. ``` ==2567752==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x5020003ed098 at pc 0x5621a816654e bp 0x7fffb55d4da0 sp 0x7fffb55d4d98 READ of size 4 at 0x5020003eee78 thread T0 #0 0x558265d6654d in aggr_cpu_id__is_empty tools/perf/util/cpumap.c:694:12 #1 0x558265c914da in perf_stat__get_aggr tools/perf/builtin-stat.c:1490:6 #2 0x558265c914da in perf_stat__get_global_cached tools/perf/builtin-stat.c:1530:9 #3 0x558265e53290 in should_skip_zero_counter tools/perf/util/stat-display.c:947:31 #4 0x558265e53290 in print_counter_aggrdata tools/perf/util/stat-display.c:985:18 #5 0x558265e51931 in print_counter tools/perf/util/stat-display.c:1110:3 torvalds#6 0x558265e51931 in evlist__print_counters tools/perf/util/stat-display.c:1571:5 torvalds#7 0x558265c8ec87 in print_counters tools/perf/builtin-stat.c:981:2 torvalds#8 0x558265c8cc71 in cmd_stat tools/perf/builtin-stat.c:2837:3 torvalds#9 0x558265bb9bd4 in run_builtin tools/perf/perf.c:323:11 torvalds#10 0x558265bb98eb in handle_internal_command tools/perf/perf.c:377:8 torvalds#11 0x558265bb9389 in run_argv tools/perf/perf.c:421:2 torvalds#12 0x558265bb9389 in main tools/perf/perf.c:537:3 ``` The issue was the use of testing a cpumap with NULL rather than using empty, as a map containing the dummy value isn't NULL and the -1 results in an empty aggr map being allocated which legitimately overflows when any member is accessed. Fixes: 8a96f45 ("perf stat: Avoid SEGV if core.cpus isn't set") Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20230906003912.3317462-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit ede72dc ] Fuzzing found that an invalid tracepoint name would create a memory leak with an address sanitizer build: ``` $ perf stat -e '*:o/' true event syntax error: '*:o/' \___ parser error Run 'perf list' for a list of valid events Usage: perf stat [<options>] [<command>] -e, --event <event> event selector. use 'perf list' to list available events ================================================================= ==59380==ERROR: LeakSanitizer: detected memory leaks Direct leak of 4 byte(s) in 2 object(s) allocated from: #0 0x7f38ac07077b in __interceptor_strdup ../../../../src/libsanitizer/asan/asan_interceptors.cpp:439 #1 0x55f2f41be73b in str util/parse-events.l:49 #2 0x55f2f41d08e8 in parse_events_lex util/parse-events.l:338 #3 0x55f2f41dc3b1 in parse_events_parse util/parse-events-bison.c:1464 #4 0x55f2f410b8b3 in parse_events__scanner util/parse-events.c:1822 #5 0x55f2f410d1b9 in __parse_events util/parse-events.c:2094 torvalds#6 0x55f2f410e57f in parse_events_option util/parse-events.c:2279 torvalds#7 0x55f2f4427b56 in get_value tools/lib/subcmd/parse-options.c:251 torvalds#8 0x55f2f4428d98 in parse_short_opt tools/lib/subcmd/parse-options.c:351 torvalds#9 0x55f2f4429d80 in parse_options_step tools/lib/subcmd/parse-options.c:539 torvalds#10 0x55f2f442acb9 in parse_options_subcommand tools/lib/subcmd/parse-options.c:654 torvalds#11 0x55f2f3ec99fc in cmd_stat tools/perf/builtin-stat.c:2501 torvalds#12 0x55f2f4093289 in run_builtin tools/perf/perf.c:322 torvalds#13 0x55f2f40937f5 in handle_internal_command tools/perf/perf.c:375 torvalds#14 0x55f2f4093bbd in run_argv tools/perf/perf.c:419 torvalds#15 0x55f2f409412b in main tools/perf/perf.c:535 SUMMARY: AddressSanitizer: 4 byte(s) leaked in 2 allocation(s). ``` Fix by adding the missing destructor. Fixes: 865582c ("perf tools: Adds the tracepoint name parsing support") Signed-off-by: Ian Rogers <irogers@google.com> Cc: He Kuang <hekuang@huawei.com> Link: https://lore.kernel.org/r/20230914164028.363220-1-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit d45c4b4 ] A thread started via eg. user_mode_thread() runs in the kernel to begin with and then may later return to userspace. While it's running in the kernel it has a pt_regs at the base of its kernel stack, but that pt_regs is all zeroes. If the thread oopses in that state, it leads to an ugly stack trace with a big block of zero GPRs, as reported by Joel: Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.5.0-rc7-00004-gf7757129e3de-dirty #3 Hardware name: IBM PowerNV (emulated by qemu) POWER9 0x4e1200 opal:v7.0 PowerNV Call Trace: [c0000000036afb00] [c0000000010dd058] dump_stack_lvl+0x6c/0x9c (unreliable) [c0000000036afb30] [c00000000013c524] panic+0x178/0x424 [c0000000036afbd0] [c000000002005100] mount_root_generic+0x250/0x324 [c0000000036afca0] [c0000000020057d0] prepare_namespace+0x2d4/0x344 [c0000000036afd20] [c0000000020049c0] kernel_init_freeable+0x358/0x3ac [c0000000036afdf0] [c0000000000111b0] kernel_init+0x30/0x1a0 [c0000000036afe50] [c00000000000debc] ret_from_kernel_user_thread+0x14/0x1c --- interrupt: 0 at 0x0 NIP: 0000000000000000 LR: 0000000000000000 CTR: 0000000000000000 REGS: c0000000036afe80 TRAP: 0000 Not tainted (6.5.0-rc7-00004-gf7757129e3de-dirty) MSR: 0000000000000000 <> CR: 00000000 XER: 00000000 CFAR: 0000000000000000 IRQMASK: 0 GPR00: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR04: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR12: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR24: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR28: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 NIP [0000000000000000] 0x0 LR [0000000000000000] 0x0 --- interrupt: 0 The all-zero pt_regs looks ugly and conveys no useful information, other than its presence. So detect that case and just show the presence of the frame by printing the interrupt marker, eg: Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.5.0-rc3-00126-g18e9506562a0-dirty torvalds#301 Hardware name: IBM pSeries (emulated by qemu) POWER9 (raw) 0x4e1202 0xf000005 of:SLOF,HEAD hv:linux,kvm pSeries Call Trace: [c000000003aabb00] [c000000001143db8] dump_stack_lvl+0x6c/0x9c (unreliable) [c000000003aabb30] [c00000000014c624] panic+0x178/0x424 [c000000003aabbd0] [c0000000020050fc] mount_root_generic+0x250/0x324 [c000000003aabca0] [c0000000020057cc] prepare_namespace+0x2d4/0x344 [c000000003aabd20] [c0000000020049bc] kernel_init_freeable+0x358/0x3ac [c000000003aabdf0] [c0000000000111b0] kernel_init+0x30/0x1a0 [c000000003aabe50] [c00000000000debc] ret_from_kernel_user_thread+0x14/0x1c --- interrupt: 0 at 0x0 To avoid ever suppressing a valid pt_regs make sure the pt_regs has a zero MSR and TRAP value, and is located at the very base of the stack. Fixes: 6895dfc ("powerpc: copy_thread fill in interrupt frame marker and back chain") Reported-by: Joel Stanley <joel@jms.id.au> Reported-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20230824064210.907266-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 34c4eff ] KMSAN reported the following uninit-value access issue: ===================================================== BUG: KMSAN: uninit-value in virtio_transport_recv_pkt+0x1dfb/0x26a0 net/vmw_vsock/virtio_transport_common.c:1421 virtio_transport_recv_pkt+0x1dfb/0x26a0 net/vmw_vsock/virtio_transport_common.c:1421 vsock_loopback_work+0x3bb/0x5a0 net/vmw_vsock/vsock_loopback.c:120 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0xff6/0x1e60 kernel/workqueue.c:2703 worker_thread+0xeca/0x14d0 kernel/workqueue.c:2784 kthread+0x3cc/0x520 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Uninit was stored to memory at: virtio_transport_space_update net/vmw_vsock/virtio_transport_common.c:1274 [inline] virtio_transport_recv_pkt+0x1ee8/0x26a0 net/vmw_vsock/virtio_transport_common.c:1415 vsock_loopback_work+0x3bb/0x5a0 net/vmw_vsock/vsock_loopback.c:120 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0xff6/0x1e60 kernel/workqueue.c:2703 worker_thread+0xeca/0x14d0 kernel/workqueue.c:2784 kthread+0x3cc/0x520 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Uninit was created at: slab_post_alloc_hook+0x105/0xad0 mm/slab.h:767 slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x5a2/0xaf0 mm/slub.c:3523 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:559 __alloc_skb+0x2fd/0x770 net/core/skbuff.c:650 alloc_skb include/linux/skbuff.h:1286 [inline] virtio_vsock_alloc_skb include/linux/virtio_vsock.h:66 [inline] virtio_transport_alloc_skb+0x90/0x11e0 net/vmw_vsock/virtio_transport_common.c:58 virtio_transport_reset_no_sock net/vmw_vsock/virtio_transport_common.c:957 [inline] virtio_transport_recv_pkt+0x1279/0x26a0 net/vmw_vsock/virtio_transport_common.c:1387 vsock_loopback_work+0x3bb/0x5a0 net/vmw_vsock/vsock_loopback.c:120 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0xff6/0x1e60 kernel/workqueue.c:2703 worker_thread+0xeca/0x14d0 kernel/workqueue.c:2784 kthread+0x3cc/0x520 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 CPU: 1 PID: 10664 Comm: kworker/1:5 Not tainted 6.6.0-rc3-00146-g9f3ebbef746f #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc38 04/01/2014 Workqueue: vsock-loopback vsock_loopback_work ===================================================== The following simple reproducer can cause the issue described above: int main(void) { int sock; struct sockaddr_vm addr = { .svm_family = AF_VSOCK, .svm_cid = VMADDR_CID_ANY, .svm_port = 1234, }; sock = socket(AF_VSOCK, SOCK_STREAM, 0); connect(sock, (struct sockaddr *)&addr, sizeof(addr)); return 0; } This issue occurs because the `buf_alloc` and `fwd_cnt` fields of the `struct virtio_vsock_hdr` are not initialized when a new skb is allocated in `virtio_transport_init_hdr()`. This patch resolves the issue by initializing these fields during allocation. Fixes: 71dc9ec ("virtio/vsock: replace virtio_vsock_pkt with sk_buff") Reported-and-tested-by: syzbot+0c8ce1da0ac31abbadcd@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=0c8ce1da0ac31abbadcd Signed-off-by: Shigeru Yoshida <syoshida@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://lore.kernel.org/r/20231104150531.257952-1-syoshida@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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Andrii Nakryiko says: ==================== BPF control flow graph and precision backtrack fixes A small fix to BPF verifier's CFG logic around handling and reporting ldimm64 instructions. Patch #1 was previously submitted separately ([0]), and so this patch set supersedes that patch. Second patch is fixing obscure corner case in mark_chain_precise() logic. See patch for details. Patch #3 adds a dedicated test, however fragile it might. [0] https://patchwork.kernel.org/project/netdevbpf/patch/20231101205626.119243-1-andrii@kernel.org/ ==================== Link: https://lore.kernel.org/r/20231110002638.4168352-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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Nov 27, 2023
This allows it to break the following circular locking dependency. Aug 10 07:01:29 dg1test kernel: ====================================================== Aug 10 07:01:29 dg1test kernel: WARNING: possible circular locking dependency detected Aug 10 07:01:29 dg1test kernel: 6.4.0-rc7+ torvalds#10 Not tainted Aug 10 07:01:29 dg1test kernel: ------------------------------------------------------ Aug 10 07:01:29 dg1test kernel: wireplumber/2236 is trying to acquire lock: Aug 10 07:01:29 dg1test kernel: ffff8fca5320da18 (&fctx->lock){-...}-{2:2}, at: nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: but task is already holding lock: Aug 10 07:01:29 dg1test kernel: ffff8fca41208610 (&event->list_lock#2){-...}-{2:2}, at: nvkm_event_ntfy+0x50/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: which lock already depends on the new lock. Aug 10 07:01:29 dg1test kernel: the existing dependency chain (in reverse order) is: Aug 10 07:01:29 dg1test kernel: -> #3 (&event->list_lock#2){-...}-{2:2}: Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy+0x50/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: ga100_fifo_nonstall_intr+0x24/0x30 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_intr+0x12c/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: __handle_irq_event_percpu+0x88/0x240 Aug 10 07:01:29 dg1test kernel: handle_irq_event+0x38/0x80 Aug 10 07:01:29 dg1test kernel: handle_edge_irq+0xa3/0x240 Aug 10 07:01:29 dg1test kernel: __common_interrupt+0x72/0x160 Aug 10 07:01:29 dg1test kernel: common_interrupt+0x60/0xe0 Aug 10 07:01:29 dg1test kernel: asm_common_interrupt+0x26/0x40 Aug 10 07:01:29 dg1test kernel: -> #2 (&device->intr.lock){-...}-{2:2}: Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nvkm_inth_allow+0x2c/0x80 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_state+0x181/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_allow+0x63/0xd0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_uevent_mthd+0x4d/0x70 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_ioctl+0x10b/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_object_mthd+0xa8/0x1f0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_event_allow+0x2a/0xa0 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_fence_enable_signaling+0x78/0x80 [nouveau] Aug 10 07:01:29 dg1test kernel: __dma_fence_enable_signaling+0x5e/0x100 Aug 10 07:01:29 dg1test kernel: dma_fence_add_callback+0x4b/0xd0 Aug 10 07:01:29 dg1test kernel: nouveau_cli_work_queue+0xae/0x110 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_gem_object_close+0x1d1/0x2a0 [nouveau] Aug 10 07:01:29 dg1test kernel: drm_gem_handle_delete+0x70/0xe0 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl_kernel+0xa5/0x150 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl+0x256/0x490 [drm] Aug 10 07:01:29 dg1test kernel: nouveau_drm_ioctl+0x5a/0xb0 [nouveau] Aug 10 07:01:29 dg1test kernel: __x64_sys_ioctl+0x91/0xd0 Aug 10 07:01:29 dg1test kernel: do_syscall_64+0x3c/0x90 Aug 10 07:01:29 dg1test kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Aug 10 07:01:29 dg1test kernel: -> #1 (&event->refs_lock#4){....}-{2:2}: Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_state+0x37/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_allow+0x63/0xd0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_uevent_mthd+0x4d/0x70 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_ioctl+0x10b/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_object_mthd+0xa8/0x1f0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_event_allow+0x2a/0xa0 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_fence_enable_signaling+0x78/0x80 [nouveau] Aug 10 07:01:29 dg1test kernel: __dma_fence_enable_signaling+0x5e/0x100 Aug 10 07:01:29 dg1test kernel: dma_fence_add_callback+0x4b/0xd0 Aug 10 07:01:29 dg1test kernel: nouveau_cli_work_queue+0xae/0x110 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_gem_object_close+0x1d1/0x2a0 [nouveau] Aug 10 07:01:29 dg1test kernel: drm_gem_handle_delete+0x70/0xe0 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl_kernel+0xa5/0x150 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl+0x256/0x490 [drm] Aug 10 07:01:29 dg1test kernel: nouveau_drm_ioctl+0x5a/0xb0 [nouveau] Aug 10 07:01:29 dg1test kernel: __x64_sys_ioctl+0x91/0xd0 Aug 10 07:01:29 dg1test kernel: do_syscall_64+0x3c/0x90 Aug 10 07:01:29 dg1test kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Aug 10 07:01:29 dg1test kernel: -> #0 (&fctx->lock){-...}-{2:2}: Aug 10 07:01:29 dg1test kernel: __lock_acquire+0x14e3/0x2240 Aug 10 07:01:29 dg1test kernel: lock_acquire+0xc8/0x2a0 Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_client_event+0xf/0x20 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy+0x9b/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: ga100_fifo_nonstall_intr+0x24/0x30 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_intr+0x12c/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: __handle_irq_event_percpu+0x88/0x240 Aug 10 07:01:29 dg1test kernel: handle_irq_event+0x38/0x80 Aug 10 07:01:29 dg1test kernel: handle_edge_irq+0xa3/0x240 Aug 10 07:01:29 dg1test kernel: __common_interrupt+0x72/0x160 Aug 10 07:01:29 dg1test kernel: common_interrupt+0x60/0xe0 Aug 10 07:01:29 dg1test kernel: asm_common_interrupt+0x26/0x40 Aug 10 07:01:29 dg1test kernel: other info that might help us debug this: Aug 10 07:01:29 dg1test kernel: Chain exists of: &fctx->lock --> &device->intr.lock --> &event->list_lock#2 Aug 10 07:01:29 dg1test kernel: Possible unsafe locking scenario: Aug 10 07:01:29 dg1test kernel: CPU0 CPU1 Aug 10 07:01:29 dg1test kernel: ---- ---- Aug 10 07:01:29 dg1test kernel: lock(&event->list_lock#2); Aug 10 07:01:29 dg1test kernel: lock(&device->intr.lock); Aug 10 07:01:29 dg1test kernel: lock(&event->list_lock#2); Aug 10 07:01:29 dg1test kernel: lock(&fctx->lock); Aug 10 07:01:29 dg1test kernel: *** DEADLOCK *** Aug 10 07:01:29 dg1test kernel: 2 locks held by wireplumber/2236: Aug 10 07:01:29 dg1test kernel: #0: ffff8fca53177bf8 (&device->intr.lock){-...}-{2:2}, at: nvkm_intr+0x29/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: #1: ffff8fca41208610 (&event->list_lock#2){-...}-{2:2}, at: nvkm_event_ntfy+0x50/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: stack backtrace: Aug 10 07:01:29 dg1test kernel: CPU: 6 PID: 2236 Comm: wireplumber Not tainted 6.4.0-rc7+ torvalds#10 Aug 10 07:01:29 dg1test kernel: Hardware name: Gigabyte Technology Co., Ltd. Z390 I AORUS PRO WIFI/Z390 I AORUS PRO WIFI-CF, BIOS F8 11/05/2021 Aug 10 07:01:29 dg1test kernel: Call Trace: Aug 10 07:01:29 dg1test kernel: <TASK> Aug 10 07:01:29 dg1test kernel: dump_stack_lvl+0x5b/0x90 Aug 10 07:01:29 dg1test kernel: check_noncircular+0xe2/0x110 Aug 10 07:01:29 dg1test kernel: __lock_acquire+0x14e3/0x2240 Aug 10 07:01:29 dg1test kernel: lock_acquire+0xc8/0x2a0 Aug 10 07:01:29 dg1test kernel: ? nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: ? lock_acquire+0xc8/0x2a0 Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: ? nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_client_event+0xf/0x20 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy+0x9b/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: ga100_fifo_nonstall_intr+0x24/0x30 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_intr+0x12c/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: __handle_irq_event_percpu+0x88/0x240 Aug 10 07:01:29 dg1test kernel: handle_irq_event+0x38/0x80 Aug 10 07:01:29 dg1test kernel: handle_edge_irq+0xa3/0x240 Aug 10 07:01:29 dg1test kernel: __common_interrupt+0x72/0x160 Aug 10 07:01:29 dg1test kernel: common_interrupt+0x60/0xe0 Aug 10 07:01:29 dg1test kernel: asm_common_interrupt+0x26/0x40 Aug 10 07:01:29 dg1test kernel: RIP: 0033:0x7fb66174d700 Aug 10 07:01:29 dg1test kernel: Code: c1 e2 05 29 ca 8d 0c 10 0f be 07 84 c0 75 eb 89 c8 c3 0f 1f 84 00 00 00 00 00 f3 0f 1e fa e9 d7 0f fc ff 0f 1f 80 00 00 00 00 <f3> 0f 1e fa e9 c7 0f fc> Aug 10 07:01:29 dg1test kernel: RSP: 002b:00007ffdd3c48438 EFLAGS: 00000206 Aug 10 07:01:29 dg1test kernel: RAX: 000055bb758763c0 RBX: 000055bb758752c0 RCX: 00000000000028b0 Aug 10 07:01:29 dg1test kernel: RDX: 000055bb758752c0 RSI: 000055bb75887490 RDI: 000055bb75862950 Aug 10 07:01:29 dg1test kernel: RBP: 00007ffdd3c48490 R08: 000055bb75873b10 R09: 0000000000000001 Aug 10 07:01:29 dg1test kernel: R10: 0000000000000004 R11: 000055bb7587f000 R12: 000055bb75887490 Aug 10 07:01:29 dg1test kernel: R13: 000055bb757f6280 R14: 000055bb758875c0 R15: 000055bb757f6280 Aug 10 07:01:29 dg1test kernel: </TASK> Signed-off-by: Dave Airlie <airlied@redhat.com> Tested-by: Danilo Krummrich <dakr@redhat.com> Reviewed-by: Danilo Krummrich <dakr@redhat.com> Signed-off-by: Danilo Krummrich <dakr@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20231107053255.2257079-1-airlied@gmail.com
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…f-times'
Eduard Zingerman says:
====================
verify callbacks as if they are called unknown number of times
This series updates verifier logic for callback functions handling.
Current master simulates callback body execution exactly once,
which leads to verifier not detecting unsafe programs like below:
static int unsafe_on_zero_iter_cb(__u32 idx, struct num_context *ctx)
{
ctx->i = 0;
return 0;
}
SEC("?raw_tp")
int unsafe_on_zero_iter(void *unused)
{
struct num_context loop_ctx = { .i = 32 };
__u8 choice_arr[2] = { 0, 1 };
bpf_loop(100, unsafe_on_zero_iter_cb, &loop_ctx, 0);
return choice_arr[loop_ctx.i];
}
This was reported previously in [0].
The basic idea of the fix is to schedule callback entry state for
verification in env->head until some identical, previously visited
state in current DFS state traversal is found. Same logic as with open
coded iterators, and builds on top recent fixes [1] for those.
The series is structured as follows:
- patches #1,2,3 update strobemeta, xdp_synproxy selftests and
bpf_loop_bench benchmark to allow convergence of the bpf_loop
callback states;
- patches #4,5 just shuffle the code a bit;
- patch torvalds#6 is the main part of the series;
- patch torvalds#7 adds test cases for torvalds#6;
- patch torvalds#8 extend patch torvalds#6 with same speculative scalar widening
logic, as used for open coded iterators;
- patch torvalds#9 adds test cases for torvalds#8;
- patch torvalds#10 extends patch torvalds#6 to track maximal number of callback
executions specifically for bpf_loop();
- patch torvalds#11 adds test cases for torvalds#10.
Veristat results comparing this series to master+patches #1,2,3 using selftests
show the following difference:
File Program States (A) States (B) States (DIFF)
------------------------- ------------- ---------- ---------- -------------
bpf_loop_bench.bpf.o benchmark 1 2 +1 (+100.00%)
pyperf600_bpf_loop.bpf.o on_event 322 407 +85 (+26.40%)
strobemeta_bpf_loop.bpf.o on_event 113 151 +38 (+33.63%)
xdp_synproxy_kern.bpf.o syncookie_tc 341 291 -50 (-14.66%)
xdp_synproxy_kern.bpf.o syncookie_xdp 344 301 -43 (-12.50%)
Veristat results comparing this series to master using Tetragon BPF
files [2] also show some differences.
States diff varies from +2% to +15% on 23 programs out of 186,
no new failures.
Changelog:
- V3 [5] -> V4, changes suggested by Andrii:
- validate mark_chain_precision() result in patch torvalds#10;
- renaming s/cumulative_callback_depth/callback_unroll_depth/.
- V2 [4] -> V3:
- fixes in expected log messages for test cases:
- callback_result_precise;
- parent_callee_saved_reg_precise_with_callback;
- parent_stack_slot_precise_with_callback;
- renamings (suggested by Alexei):
- s/callback_iter_depth/cumulative_callback_depth/
- s/is_callback_iter_next/calls_callback/
- s/mark_callback_iter_next/mark_calls_callback/
- prepare_func_exit() updated to exit with -EFAULT when
callee->in_callback_fn is true but calls_callback() is not true
for callsite;
- test case 'bpf_loop_iter_limit_nested' rewritten to use return
value check instead of verifier log message checks
(suggested by Alexei).
- V1 [3] -> V2, changes suggested by Andrii:
- small changes for error handling code in __check_func_call();
- callback body processing log is now matched in relevant
verifier_subprog_precision.c tests;
- R1 passed to bpf_loop() is now always marked as precise;
- log level 2 message for bpf_loop() iteration termination instead of
iteration depth messages;
- __no_msg macro removed;
- bpf_loop_iter_limit_nested updated to avoid using __no_msg;
- commit message for patch #3 updated according to Alexei's request.
[0] https://lore.kernel.org/bpf/CA+vRuzPChFNXmouzGG+wsy=6eMcfr1mFG0F3g7rbg-sedGKW3w@mail.gmail.com/
[1] https://lore.kernel.org/bpf/20231024000917.12153-1-eddyz87@gmail.com/
[2] git@github.com:cilium/tetragon.git
[3] https://lore.kernel.org/bpf/20231116021803.9982-1-eddyz87@gmail.com/T/#t
[4] https://lore.kernel.org/bpf/20231118013355.7943-1-eddyz87@gmail.com/T/#t
[5] https://lore.kernel.org/bpf/20231120225945.11741-1-eddyz87@gmail.com/T/#t
====================
Link: https://lore.kernel.org/r/20231121020701.26440-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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commit dd976a9 upstream. The smp_processor_id() shouldn't be called from preemptible code. Instead use get_cpu() and put_cpu() which disables preemption in addition to getting the processor id. Enable preemption back after calling schedule_work() to make sure that the work gets scheduled on all cores other than the current core. We want to avoid a scenario where current core's stack trace is printed multiple times and one core's stack trace isn't printed because of scheduling of current task. This fixes the following bug: [ 119.143590] sysrq: Show backtrace of all active CPUs [ 119.143902] BUG: using smp_processor_id() in preemptible [00000000] code: bash/873 [ 119.144586] caller is debug_smp_processor_id+0x20/0x30 [ 119.144827] CPU: 6 PID: 873 Comm: bash Not tainted 5.10.124-dirty #3 [ 119.144861] Hardware name: QEMU QEMU Virtual Machine, BIOS 2023.05-1 07/22/2023 [ 119.145053] Call trace: [ 119.145093] dump_backtrace+0x0/0x1a0 [ 119.145122] show_stack+0x18/0x70 [ 119.145141] dump_stack+0xc4/0x11c [ 119.145159] check_preemption_disabled+0x100/0x110 [ 119.145175] debug_smp_processor_id+0x20/0x30 [ 119.145195] sysrq_handle_showallcpus+0x20/0xc0 [ 119.145211] __handle_sysrq+0x8c/0x1a0 [ 119.145227] write_sysrq_trigger+0x94/0x12c [ 119.145247] proc_reg_write+0xa8/0xe4 [ 119.145266] vfs_write+0xec/0x280 [ 119.145282] ksys_write+0x6c/0x100 [ 119.145298] __arm64_sys_write+0x20/0x30 [ 119.145315] el0_svc_common.constprop.0+0x78/0x1e4 [ 119.145332] do_el0_svc+0x24/0x8c [ 119.145348] el0_svc+0x10/0x20 [ 119.145364] el0_sync_handler+0x134/0x140 [ 119.145381] el0_sync+0x180/0x1c0 Cc: jirislaby@kernel.org Cc: stable@vger.kernel.org Fixes: 47cab6a ("debug lockups: Improve lockup detection, fix generic arch fallback") Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Link: https://lore.kernel.org/r/20231009162021.3607632-1-usama.anjum@collabora.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 807252f upstream. Running smb2.rename test from Samba smbtorture suite against a kernel built with lockdep triggers a "possible recursive locking detected" warning. This is because mnt_want_write() is called twice with no mnt_drop_write() in between: -> ksmbd_vfs_mkdir() -> ksmbd_vfs_kern_path_create() -> kern_path_create() -> filename_create() -> mnt_want_write() -> mnt_want_write() Fix this by removing the mnt_want_write/mnt_drop_write calls from vfs helpers that call kern_path_create(). Full lockdep trace below: ============================================ WARNING: possible recursive locking detected 6.6.0-rc5 torvalds#775 Not tainted -------------------------------------------- kworker/1:1/32 is trying to acquire lock: ffff888005ac83f8 (sb_writers#5){.+.+}-{0:0}, at: ksmbd_vfs_mkdir+0xe1/0x410 but task is already holding lock: ffff888005ac83f8 (sb_writers#5){.+.+}-{0:0}, at: filename_create+0xb6/0x260 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(sb_writers#5); lock(sb_writers#5); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by kworker/1:1/32: #0: ffff8880064e4138 ((wq_completion)ksmbd-io){+.+.}-{0:0}, at: process_one_work+0x40e/0x980 #1: ffff888005b0fdd0 ((work_completion)(&work->work)){+.+.}-{0:0}, at: process_one_work+0x40e/0x980 #2: ffff888005ac83f8 (sb_writers#5){.+.+}-{0:0}, at: filename_create+0xb6/0x260 #3: ffff8880057ce760 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: filename_create+0x123/0x260 Cc: stable@vger.kernel.org Fixes: 40b268d ("ksmbd: add mnt_want_write to ksmbd vfs functions") Signed-off-by: Marios Makassikis <mmakassikis@freebox.fr> Acked-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Nov 29, 2023
commit 5a22fbc upstream. When LAN9303 is MDIO-connected two callchains exist into mdio->bus->write(): 1. switch ports 1&2 ("physical" PHYs): virtual (switch-internal) MDIO bus (lan9303_switch_ops->phy_{read|write})-> lan9303_mdio_phy_{read|write} -> mdiobus_{read|write}_nested 2. LAN9303 virtual PHY: virtual MDIO bus (lan9303_phy_{read|write}) -> lan9303_virt_phy_reg_{read|write} -> regmap -> lan9303_mdio_{read|write} If the latter functions just take mutex_lock(&sw_dev->device->bus->mdio_lock) it triggers a LOCKDEP false-positive splat. It's false-positive because the first mdio_lock in the second callchain above belongs to virtual MDIO bus, the second mdio_lock belongs to physical MDIO bus. Consequent annotation in lan9303_mdio_{read|write} as nested lock (similar to lan9303_mdio_phy_{read|write}, it's the same physical MDIO bus) prevents the following splat: WARNING: possible circular locking dependency detected 5.15.71 #1 Not tainted ------------------------------------------------------ kworker/u4:3/609 is trying to acquire lock: ffff000011531c68 (lan9303_mdio:131:(&lan9303_mdio_regmap_config)->lock){+.+.}-{3:3}, at: regmap_lock_mutex but task is already holding lock: ffff0000114c44d8 (&bus->mdio_lock){+.+.}-{3:3}, at: mdiobus_read which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&bus->mdio_lock){+.+.}-{3:3}: lock_acquire __mutex_lock mutex_lock_nested lan9303_mdio_read _regmap_read regmap_read lan9303_probe lan9303_mdio_probe mdio_probe really_probe __driver_probe_device driver_probe_device __device_attach_driver bus_for_each_drv __device_attach device_initial_probe bus_probe_device deferred_probe_work_func process_one_work worker_thread kthread ret_from_fork -> #0 (lan9303_mdio:131:(&lan9303_mdio_regmap_config)->lock){+.+.}-{3:3}: __lock_acquire lock_acquire.part.0 lock_acquire __mutex_lock mutex_lock_nested regmap_lock_mutex regmap_read lan9303_phy_read dsa_slave_phy_read __mdiobus_read mdiobus_read get_phy_device mdiobus_scan __mdiobus_register dsa_register_switch lan9303_probe lan9303_mdio_probe mdio_probe really_probe __driver_probe_device driver_probe_device __device_attach_driver bus_for_each_drv __device_attach device_initial_probe bus_probe_device deferred_probe_work_func process_one_work worker_thread kthread ret_from_fork other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&bus->mdio_lock); lock(lan9303_mdio:131:(&lan9303_mdio_regmap_config)->lock); lock(&bus->mdio_lock); lock(lan9303_mdio:131:(&lan9303_mdio_regmap_config)->lock); *** DEADLOCK *** 5 locks held by kworker/u4:3/609: #0: ffff000002842938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work #1: ffff80000bacbd60 (deferred_probe_work){+.+.}-{0:0}, at: process_one_work #2: ffff000007645178 (&dev->mutex){....}-{3:3}, at: __device_attach #3: ffff8000096e6e78 (dsa2_mutex){+.+.}-{3:3}, at: dsa_register_switch #4: ffff0000114c44d8 (&bus->mdio_lock){+.+.}-{3:3}, at: mdiobus_read stack backtrace: CPU: 1 PID: 609 Comm: kworker/u4:3 Not tainted 5.15.71 #1 Workqueue: events_unbound deferred_probe_work_func Call trace: dump_backtrace show_stack dump_stack_lvl dump_stack print_circular_bug check_noncircular __lock_acquire lock_acquire.part.0 lock_acquire __mutex_lock mutex_lock_nested regmap_lock_mutex regmap_read lan9303_phy_read dsa_slave_phy_read __mdiobus_read mdiobus_read get_phy_device mdiobus_scan __mdiobus_register dsa_register_switch lan9303_probe lan9303_mdio_probe ... Cc: stable@vger.kernel.org Fixes: dc70058 ("net: dsa: LAN9303: add MDIO managed mode support") Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Link: https://lore.kernel.org/r/20231027065741.534971-1-alexander.sverdlin@siemens.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When scanning namespaces, it is possible to get valid data from the first call to nvme_identify_ns() in nvme_alloc_ns(), but not from the second call in nvme_update_ns_info_block(). In particular, if the NSID becomes inactive between the two commands, a storage device may return a buffer filled with zero as per 4.1.5.1. In this case, we can get a kernel crash due to a divide-by-zero in blk_stack_limits() because ns->lba_shift will be set to zero. PID: 326 TASK: ffff95fec3cd8000 CPU: 29 COMMAND: "kworker/u98:10" #0 [ffffad8f8702f9e0] machine_kexec at ffffffff91c76ec7 #1 [ffffad8f8702fa38] __crash_kexec at ffffffff91dea4fa #2 [ffffad8f8702faf8] crash_kexec at ffffffff91deb788 #3 [ffffad8f8702fb00] oops_end at ffffffff91c2e4bb #4 [ffffad8f8702fb20] do_trap at ffffffff91c2a4ce #5 [ffffad8f8702fb70] do_error_trap at ffffffff91c2a595 torvalds#6 [ffffad8f8702fbb0] exc_divide_error at ffffffff928506e6 torvalds#7 [ffffad8f8702fbd0] asm_exc_divide_error at ffffffff92a00926 [exception RIP: blk_stack_limits+434] RIP: ffffffff92191872 RSP: ffffad8f8702fc80 RFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff95efa0c91800 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: 00000000ffffffff R8: ffff95fec7df35a8 R9: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff95fed33c09a8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 torvalds#8 [ffffad8f8702fce0] nvme_update_ns_info_block at ffffffffc06d3533 [nvme_core] torvalds#9 [ffffad8f8702fd18] nvme_scan_ns at ffffffffc06d6fa7 [nvme_core] This happened when the check for valid data was moved out of nvme_identify_ns() into one of the callers. Fix this by checking in both callers. Link: https://bugzilla.kernel.org/show_bug.cgi?id=218186 Fixes: 0dd6fff ("nvme: bring back auto-removal of deleted namespaces during sequential scan") Cc: stable@vger.kernel.org Signed-off-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: Keith Busch <kbusch@kernel.org>
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Dec 8, 2023
commit d8b90d6 upstream. When scanning namespaces, it is possible to get valid data from the first call to nvme_identify_ns() in nvme_alloc_ns(), but not from the second call in nvme_update_ns_info_block(). In particular, if the NSID becomes inactive between the two commands, a storage device may return a buffer filled with zero as per 4.1.5.1. In this case, we can get a kernel crash due to a divide-by-zero in blk_stack_limits() because ns->lba_shift will be set to zero. PID: 326 TASK: ffff95fec3cd8000 CPU: 29 COMMAND: "kworker/u98:10" #0 [ffffad8f8702f9e0] machine_kexec at ffffffff91c76ec7 #1 [ffffad8f8702fa38] __crash_kexec at ffffffff91dea4fa #2 [ffffad8f8702faf8] crash_kexec at ffffffff91deb788 #3 [ffffad8f8702fb00] oops_end at ffffffff91c2e4bb #4 [ffffad8f8702fb20] do_trap at ffffffff91c2a4ce #5 [ffffad8f8702fb70] do_error_trap at ffffffff91c2a595 torvalds#6 [ffffad8f8702fbb0] exc_divide_error at ffffffff928506e6 torvalds#7 [ffffad8f8702fbd0] asm_exc_divide_error at ffffffff92a00926 [exception RIP: blk_stack_limits+434] RIP: ffffffff92191872 RSP: ffffad8f8702fc80 RFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff95efa0c91800 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: 00000000ffffffff R8: ffff95fec7df35a8 R9: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff95fed33c09a8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 torvalds#8 [ffffad8f8702fce0] nvme_update_ns_info_block at ffffffffc06d3533 [nvme_core] torvalds#9 [ffffad8f8702fd18] nvme_scan_ns at ffffffffc06d6fa7 [nvme_core] This happened when the check for valid data was moved out of nvme_identify_ns() into one of the callers. Fix this by checking in both callers. Link: https://bugzilla.kernel.org/show_bug.cgi?id=218186 Fixes: 0dd6fff ("nvme: bring back auto-removal of deleted namespaces during sequential scan") Cc: stable@vger.kernel.org Signed-off-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Dec 11, 2023
When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be dereferenced as wrong struct in irdma_free_pending_cqp_request(). PID: 3669 TASK: ffff88aef892c000 CPU: 28 COMMAND: "kworker/28:0" #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34 #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2 #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f #3 [fffffe0000549eb8] do_nmi at ffffffff81079582 #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4 [exception RIP: native_queued_spin_lock_slowpath+1291] RIP: ffffffff8127e72b RSP: ffff88aa841ef778 RFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88b01f849700 RCX: ffffffff8127e47e RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff83857ec0 RBP: ffff88afe3e4efc8 R8: ffffed15fc7c9dfa R9: ffffed15fc7c9dfa R10: 0000000000000001 R11: ffffed15fc7c9df9 R12: 0000000000740000 R13: ffff88b01f849708 R14: 0000000000000003 R15: ffffed1603f092e1 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 -- <NMI exception stack> -- #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b torvalds#6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4 torvalds#7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363 torvalds#8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma] torvalds#9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma] torvalds#10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma] torvalds#11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma] torvalds#12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb torvalds#13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6 torvalds#14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278 torvalds#15 [ffff88aa841efb88] device_del at ffffffff82179d23 torvalds#16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice] torvalds#17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice] torvalds#18 [ffff88aa841efde8] process_one_work at ffffffff811c589a torvalds#19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff torvalds#20 [ffff88aa841eff10] kthread at ffffffff811d87a0 torvalds#21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions") Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com> Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn> Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
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When working on LED support for r8169 I got the following lockdep warning. Easiest way to prevent this scenario seems to be to take the RTNL lock before the trigger_data lock in set_device_name(). ====================================================== WARNING: possible circular locking dependency detected 6.7.0-rc2-next-20231124+ #2 Not tainted ------------------------------------------------------ bash/383 is trying to acquire lock: ffff888103aa1c68 (&trigger_data->lock){+.+.}-{3:3}, at: netdev_trig_notify+0xec/0x190 [ledtrig_netdev] but task is already holding lock: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (rtnl_mutex){+.+.}-{3:3}: __mutex_lock+0x9b/0xb50 mutex_lock_nested+0x16/0x20 rtnl_lock+0x12/0x20 set_device_name+0xa9/0x120 [ledtrig_netdev] netdev_trig_activate+0x1a1/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 -> #0 (&trigger_data->lock){+.+.}-{3:3}: __lock_acquire+0x1459/0x25a0 lock_acquire+0xc8/0x2d0 __mutex_lock+0x9b/0xb50 mutex_lock_nested+0x16/0x20 netdev_trig_notify+0xec/0x190 [ledtrig_netdev] call_netdevice_register_net_notifiers+0x5a/0x100 register_netdevice_notifier+0x85/0x120 netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rtnl_mutex); lock(&trigger_data->lock); lock(rtnl_mutex); lock(&trigger_data->lock); *** DEADLOCK *** 8 locks held by bash/383: #0: ffff888103ff33f0 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x6c/0xf0 #1: ffff888103aa1e88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x114/0x210 #2: ffff8881036f1890 (kn->active#82){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x11d/0x210 #3: ffff888108e2c358 (&led_cdev->led_access){+.+.}-{3:3}, at: led_trigger_write+0x30/0x140 #4: ffffffff8cdd9e10 (triggers_list_lock){++++}-{3:3}, at: led_trigger_write+0x75/0x140 #5: ffff888108e2c270 (&led_cdev->trigger_lock){++++}-{3:3}, at: led_trigger_write+0xe3/0x140 torvalds#6: ffffffff8cdde3d0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1c/0x120 torvalds#7: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20 stack backtrace: CPU: 0 PID: 383 Comm: bash Not tainted 6.7.0-rc2-next-20231124+ #2 Hardware name: Default string Default string/Default string, BIOS ADLN.M6.SODIMM.ZB.CY.015 08/08/2023 Call Trace: <TASK> dump_stack_lvl+0x5c/0xd0 dump_stack+0x10/0x20 print_circular_bug+0x2dd/0x410 check_noncircular+0x131/0x150 __lock_acquire+0x1459/0x25a0 lock_acquire+0xc8/0x2d0 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] __mutex_lock+0x9b/0xb50 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] ? __this_cpu_preempt_check+0x13/0x20 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] ? __cancel_work_timer+0x11c/0x1b0 ? __mutex_lock+0x123/0xb50 mutex_lock_nested+0x16/0x20 ? mutex_lock_nested+0x16/0x20 netdev_trig_notify+0xec/0x190 [ledtrig_netdev] call_netdevice_register_net_notifiers+0x5a/0x100 register_netdevice_notifier+0x85/0x120 netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 ? preempt_count_add+0x49/0xc0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 RIP: 0033:0x7f269055d034 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d 35 c3 0d 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 48 89 54 24 18 48 RSP: 002b:00007ffddb7ef748 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007f269055d034 RDX: 0000000000000007 RSI: 000055bf5f4af3c0 RDI: 0000000000000001 RBP: 000055bf5f4af3c0 R08: 0000000000000073 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000007 R13: 00007f26906325c0 R14: 00007f269062ff20 R15: 0000000000000000 </TASK> Fixes: d5e0126 ("leds: trigger: netdev: add additional specific link speed mode") Cc: stable@vger.kernel.org Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Acked-by: Lee Jones <lee@kernel.org> Link: https://lore.kernel.org/r/fb5c8294-2a10-4bf5-8f10-3d2b77d2757e@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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[ Upstream commit a2e36cd ] This allows it to break the following circular locking dependency. Aug 10 07:01:29 dg1test kernel: ====================================================== Aug 10 07:01:29 dg1test kernel: WARNING: possible circular locking dependency detected Aug 10 07:01:29 dg1test kernel: 6.4.0-rc7+ torvalds#10 Not tainted Aug 10 07:01:29 dg1test kernel: ------------------------------------------------------ Aug 10 07:01:29 dg1test kernel: wireplumber/2236 is trying to acquire lock: Aug 10 07:01:29 dg1test kernel: ffff8fca5320da18 (&fctx->lock){-...}-{2:2}, at: nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: but task is already holding lock: Aug 10 07:01:29 dg1test kernel: ffff8fca41208610 (&event->list_lock#2){-...}-{2:2}, at: nvkm_event_ntfy+0x50/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: which lock already depends on the new lock. Aug 10 07:01:29 dg1test kernel: the existing dependency chain (in reverse order) is: Aug 10 07:01:29 dg1test kernel: -> #3 (&event->list_lock#2){-...}-{2:2}: Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy+0x50/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: ga100_fifo_nonstall_intr+0x24/0x30 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_intr+0x12c/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: __handle_irq_event_percpu+0x88/0x240 Aug 10 07:01:29 dg1test kernel: handle_irq_event+0x38/0x80 Aug 10 07:01:29 dg1test kernel: handle_edge_irq+0xa3/0x240 Aug 10 07:01:29 dg1test kernel: __common_interrupt+0x72/0x160 Aug 10 07:01:29 dg1test kernel: common_interrupt+0x60/0xe0 Aug 10 07:01:29 dg1test kernel: asm_common_interrupt+0x26/0x40 Aug 10 07:01:29 dg1test kernel: -> #2 (&device->intr.lock){-...}-{2:2}: Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nvkm_inth_allow+0x2c/0x80 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_state+0x181/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_allow+0x63/0xd0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_uevent_mthd+0x4d/0x70 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_ioctl+0x10b/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_object_mthd+0xa8/0x1f0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_event_allow+0x2a/0xa0 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_fence_enable_signaling+0x78/0x80 [nouveau] Aug 10 07:01:29 dg1test kernel: __dma_fence_enable_signaling+0x5e/0x100 Aug 10 07:01:29 dg1test kernel: dma_fence_add_callback+0x4b/0xd0 Aug 10 07:01:29 dg1test kernel: nouveau_cli_work_queue+0xae/0x110 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_gem_object_close+0x1d1/0x2a0 [nouveau] Aug 10 07:01:29 dg1test kernel: drm_gem_handle_delete+0x70/0xe0 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl_kernel+0xa5/0x150 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl+0x256/0x490 [drm] Aug 10 07:01:29 dg1test kernel: nouveau_drm_ioctl+0x5a/0xb0 [nouveau] Aug 10 07:01:29 dg1test kernel: __x64_sys_ioctl+0x91/0xd0 Aug 10 07:01:29 dg1test kernel: do_syscall_64+0x3c/0x90 Aug 10 07:01:29 dg1test kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Aug 10 07:01:29 dg1test kernel: -> #1 (&event->refs_lock#4){....}-{2:2}: Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_state+0x37/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_allow+0x63/0xd0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_uevent_mthd+0x4d/0x70 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_ioctl+0x10b/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_object_mthd+0xa8/0x1f0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_event_allow+0x2a/0xa0 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_fence_enable_signaling+0x78/0x80 [nouveau] Aug 10 07:01:29 dg1test kernel: __dma_fence_enable_signaling+0x5e/0x100 Aug 10 07:01:29 dg1test kernel: dma_fence_add_callback+0x4b/0xd0 Aug 10 07:01:29 dg1test kernel: nouveau_cli_work_queue+0xae/0x110 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_gem_object_close+0x1d1/0x2a0 [nouveau] Aug 10 07:01:29 dg1test kernel: drm_gem_handle_delete+0x70/0xe0 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl_kernel+0xa5/0x150 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl+0x256/0x490 [drm] Aug 10 07:01:29 dg1test kernel: nouveau_drm_ioctl+0x5a/0xb0 [nouveau] Aug 10 07:01:29 dg1test kernel: __x64_sys_ioctl+0x91/0xd0 Aug 10 07:01:29 dg1test kernel: do_syscall_64+0x3c/0x90 Aug 10 07:01:29 dg1test kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Aug 10 07:01:29 dg1test kernel: -> #0 (&fctx->lock){-...}-{2:2}: Aug 10 07:01:29 dg1test kernel: __lock_acquire+0x14e3/0x2240 Aug 10 07:01:29 dg1test kernel: lock_acquire+0xc8/0x2a0 Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_client_event+0xf/0x20 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy+0x9b/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: ga100_fifo_nonstall_intr+0x24/0x30 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_intr+0x12c/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: __handle_irq_event_percpu+0x88/0x240 Aug 10 07:01:29 dg1test kernel: handle_irq_event+0x38/0x80 Aug 10 07:01:29 dg1test kernel: handle_edge_irq+0xa3/0x240 Aug 10 07:01:29 dg1test kernel: __common_interrupt+0x72/0x160 Aug 10 07:01:29 dg1test kernel: common_interrupt+0x60/0xe0 Aug 10 07:01:29 dg1test kernel: asm_common_interrupt+0x26/0x40 Aug 10 07:01:29 dg1test kernel: other info that might help us debug this: Aug 10 07:01:29 dg1test kernel: Chain exists of: &fctx->lock --> &device->intr.lock --> &event->list_lock#2 Aug 10 07:01:29 dg1test kernel: Possible unsafe locking scenario: Aug 10 07:01:29 dg1test kernel: CPU0 CPU1 Aug 10 07:01:29 dg1test kernel: ---- ---- Aug 10 07:01:29 dg1test kernel: lock(&event->list_lock#2); Aug 10 07:01:29 dg1test kernel: lock(&device->intr.lock); Aug 10 07:01:29 dg1test kernel: lock(&event->list_lock#2); Aug 10 07:01:29 dg1test kernel: lock(&fctx->lock); Aug 10 07:01:29 dg1test kernel: *** DEADLOCK *** Aug 10 07:01:29 dg1test kernel: 2 locks held by wireplumber/2236: Aug 10 07:01:29 dg1test kernel: #0: ffff8fca53177bf8 (&device->intr.lock){-...}-{2:2}, at: nvkm_intr+0x29/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: #1: ffff8fca41208610 (&event->list_lock#2){-...}-{2:2}, at: nvkm_event_ntfy+0x50/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: stack backtrace: Aug 10 07:01:29 dg1test kernel: CPU: 6 PID: 2236 Comm: wireplumber Not tainted 6.4.0-rc7+ torvalds#10 Aug 10 07:01:29 dg1test kernel: Hardware name: Gigabyte Technology Co., Ltd. Z390 I AORUS PRO WIFI/Z390 I AORUS PRO WIFI-CF, BIOS F8 11/05/2021 Aug 10 07:01:29 dg1test kernel: Call Trace: Aug 10 07:01:29 dg1test kernel: <TASK> Aug 10 07:01:29 dg1test kernel: dump_stack_lvl+0x5b/0x90 Aug 10 07:01:29 dg1test kernel: check_noncircular+0xe2/0x110 Aug 10 07:01:29 dg1test kernel: __lock_acquire+0x14e3/0x2240 Aug 10 07:01:29 dg1test kernel: lock_acquire+0xc8/0x2a0 Aug 10 07:01:29 dg1test kernel: ? nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: ? lock_acquire+0xc8/0x2a0 Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: ? nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_client_event+0xf/0x20 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy+0x9b/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: ga100_fifo_nonstall_intr+0x24/0x30 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_intr+0x12c/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: __handle_irq_event_percpu+0x88/0x240 Aug 10 07:01:29 dg1test kernel: handle_irq_event+0x38/0x80 Aug 10 07:01:29 dg1test kernel: handle_edge_irq+0xa3/0x240 Aug 10 07:01:29 dg1test kernel: __common_interrupt+0x72/0x160 Aug 10 07:01:29 dg1test kernel: common_interrupt+0x60/0xe0 Aug 10 07:01:29 dg1test kernel: asm_common_interrupt+0x26/0x40 Aug 10 07:01:29 dg1test kernel: RIP: 0033:0x7fb66174d700 Aug 10 07:01:29 dg1test kernel: Code: c1 e2 05 29 ca 8d 0c 10 0f be 07 84 c0 75 eb 89 c8 c3 0f 1f 84 00 00 00 00 00 f3 0f 1e fa e9 d7 0f fc ff 0f 1f 80 00 00 00 00 <f3> 0f 1e fa e9 c7 0f fc> Aug 10 07:01:29 dg1test kernel: RSP: 002b:00007ffdd3c48438 EFLAGS: 00000206 Aug 10 07:01:29 dg1test kernel: RAX: 000055bb758763c0 RBX: 000055bb758752c0 RCX: 00000000000028b0 Aug 10 07:01:29 dg1test kernel: RDX: 000055bb758752c0 RSI: 000055bb75887490 RDI: 000055bb75862950 Aug 10 07:01:29 dg1test kernel: RBP: 00007ffdd3c48490 R08: 000055bb75873b10 R09: 0000000000000001 Aug 10 07:01:29 dg1test kernel: R10: 0000000000000004 R11: 000055bb7587f000 R12: 000055bb75887490 Aug 10 07:01:29 dg1test kernel: R13: 000055bb757f6280 R14: 000055bb758875c0 R15: 000055bb757f6280 Aug 10 07:01:29 dg1test kernel: </TASK> Signed-off-by: Dave Airlie <airlied@redhat.com> Tested-by: Danilo Krummrich <dakr@redhat.com> Reviewed-by: Danilo Krummrich <dakr@redhat.com> Signed-off-by: Danilo Krummrich <dakr@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20231107053255.2257079-1-airlied@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit e3e82fc ] When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be dereferenced as wrong struct in irdma_free_pending_cqp_request(). PID: 3669 TASK: ffff88aef892c000 CPU: 28 COMMAND: "kworker/28:0" #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34 #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2 #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f #3 [fffffe0000549eb8] do_nmi at ffffffff81079582 #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4 [exception RIP: native_queued_spin_lock_slowpath+1291] RIP: ffffffff8127e72b RSP: ffff88aa841ef778 RFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88b01f849700 RCX: ffffffff8127e47e RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff83857ec0 RBP: ffff88afe3e4efc8 R8: ffffed15fc7c9dfa R9: ffffed15fc7c9dfa R10: 0000000000000001 R11: ffffed15fc7c9df9 R12: 0000000000740000 R13: ffff88b01f849708 R14: 0000000000000003 R15: ffffed1603f092e1 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 -- <NMI exception stack> -- #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b torvalds#6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4 torvalds#7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363 torvalds#8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma] torvalds#9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma] torvalds#10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma] torvalds#11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma] torvalds#12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb torvalds#13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6 torvalds#14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278 torvalds#15 [ffff88aa841efb88] device_del at ffffffff82179d23 torvalds#16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice] torvalds#17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice] torvalds#18 [ffff88aa841efde8] process_one_work at ffffffff811c589a torvalds#19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff torvalds#20 [ffff88aa841eff10] kthread at ffffffff811d87a0 torvalds#21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions") Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com> Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn> Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit fe2b122 upstream. When working on LED support for r8169 I got the following lockdep warning. Easiest way to prevent this scenario seems to be to take the RTNL lock before the trigger_data lock in set_device_name(). ====================================================== WARNING: possible circular locking dependency detected 6.7.0-rc2-next-20231124+ #2 Not tainted ------------------------------------------------------ bash/383 is trying to acquire lock: ffff888103aa1c68 (&trigger_data->lock){+.+.}-{3:3}, at: netdev_trig_notify+0xec/0x190 [ledtrig_netdev] but task is already holding lock: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (rtnl_mutex){+.+.}-{3:3}: __mutex_lock+0x9b/0xb50 mutex_lock_nested+0x16/0x20 rtnl_lock+0x12/0x20 set_device_name+0xa9/0x120 [ledtrig_netdev] netdev_trig_activate+0x1a1/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 -> #0 (&trigger_data->lock){+.+.}-{3:3}: __lock_acquire+0x1459/0x25a0 lock_acquire+0xc8/0x2d0 __mutex_lock+0x9b/0xb50 mutex_lock_nested+0x16/0x20 netdev_trig_notify+0xec/0x190 [ledtrig_netdev] call_netdevice_register_net_notifiers+0x5a/0x100 register_netdevice_notifier+0x85/0x120 netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rtnl_mutex); lock(&trigger_data->lock); lock(rtnl_mutex); lock(&trigger_data->lock); *** DEADLOCK *** 8 locks held by bash/383: #0: ffff888103ff33f0 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x6c/0xf0 #1: ffff888103aa1e88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x114/0x210 #2: ffff8881036f1890 (kn->active#82){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x11d/0x210 #3: ffff888108e2c358 (&led_cdev->led_access){+.+.}-{3:3}, at: led_trigger_write+0x30/0x140 #4: ffffffff8cdd9e10 (triggers_list_lock){++++}-{3:3}, at: led_trigger_write+0x75/0x140 #5: ffff888108e2c270 (&led_cdev->trigger_lock){++++}-{3:3}, at: led_trigger_write+0xe3/0x140 torvalds#6: ffffffff8cdde3d0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1c/0x120 torvalds#7: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20 stack backtrace: CPU: 0 PID: 383 Comm: bash Not tainted 6.7.0-rc2-next-20231124+ #2 Hardware name: Default string Default string/Default string, BIOS ADLN.M6.SODIMM.ZB.CY.015 08/08/2023 Call Trace: <TASK> dump_stack_lvl+0x5c/0xd0 dump_stack+0x10/0x20 print_circular_bug+0x2dd/0x410 check_noncircular+0x131/0x150 __lock_acquire+0x1459/0x25a0 lock_acquire+0xc8/0x2d0 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] __mutex_lock+0x9b/0xb50 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] ? __this_cpu_preempt_check+0x13/0x20 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] ? __cancel_work_timer+0x11c/0x1b0 ? __mutex_lock+0x123/0xb50 mutex_lock_nested+0x16/0x20 ? mutex_lock_nested+0x16/0x20 netdev_trig_notify+0xec/0x190 [ledtrig_netdev] call_netdevice_register_net_notifiers+0x5a/0x100 register_netdevice_notifier+0x85/0x120 netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 ? preempt_count_add+0x49/0xc0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 RIP: 0033:0x7f269055d034 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d 35 c3 0d 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 48 89 54 24 18 48 RSP: 002b:00007ffddb7ef748 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007f269055d034 RDX: 0000000000000007 RSI: 000055bf5f4af3c0 RDI: 0000000000000001 RBP: 000055bf5f4af3c0 R08: 0000000000000073 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000007 R13: 00007f26906325c0 R14: 00007f269062ff20 R15: 0000000000000000 </TASK> Fixes: d5e0126 ("leds: trigger: netdev: add additional specific link speed mode") Cc: stable@vger.kernel.org Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Acked-by: Lee Jones <lee@kernel.org> Link: https://lore.kernel.org/r/fb5c8294-2a10-4bf5-8f10-3d2b77d2757e@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 769e6a1 ] ui_browser__show() is capturing the input title that is stack allocated memory in hist_browser__run(). Avoid a use after return by strdup-ing the string. Committer notes: Further explanation from Ian Rogers: My command line using tui is: $ sudo bash -c 'rm /tmp/asan.log*; export ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a sleep 1; /tmp/perf/perf mem report' I then go to the perf annotate view and quit. This triggers the asan error (from the log file): ``` ==1254591==ERROR: AddressSanitizer: stack-use-after-return on address 0x7f2813331920 at pc 0x7f28180 65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10 READ of size 80 at 0x7f2813331920 thread T0 #0 0x7f2818065990 in __interceptor_strlen ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461 #1 0x7f2817698251 in SLsmg_write_wrapped_string (/lib/x86_64-linux-gnu/libslang.so.2+0x98251) #2 0x7f28176984b9 in SLsmg_write_nstring (/lib/x86_64-linux-gnu/libslang.so.2+0x984b9) #3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60 #4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266 #5 0x55c94045c776 in ui_browser__show ui/browser.c:288 torvalds#6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206 torvalds#7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458 torvalds#8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412 torvalds#9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527 torvalds#10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613 torvalds#11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661 torvalds#12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671 torvalds#13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141 torvalds#14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805 torvalds#15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374 torvalds#16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516 torvalds#17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350 torvalds#18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403 torvalds#19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447 torvalds#20 0x55c9400e53ad in main tools/perf/perf.c:561 torvalds#21 0x7f28170456c9 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58 torvalds#22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360 torvalds#23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId: 84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93) Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746 This frame has 1 object(s): [32, 192) 'title' (line 747) <== Memory access at offset 32 is inside this variable HINT: this may be a false positive if your program uses some custom stack unwind mechanism, swapcontext or vfork ``` hist_browser__run isn't on the stack so the asan error looks legit. There's no clean init/exit on struct ui_browser so I may be trading a use-after-return for a memory leak, but that seems look a good trade anyway. Fixes: 05e8b08 ("perf ui browser: Stop using 'self'") Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Cc: Ben Gainey <ben.gainey@arm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Li Dong <lidong@vivo.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sun Haiyong <sunhaiyong@loongson.cn> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: Yicong Yang <yangyicong@hisilicon.com> Link: https://lore.kernel.org/r/20240507183545.1236093-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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…PLES event" commit 5b3cde1 upstream. This reverts commit 7d1405c. This causes segfaults in some cases, as reported by Milian: ``` sudo /usr/bin/perf record -z --call-graph dwarf -e cycles -e raw_syscalls:sys_enter ls ... [ perf record: Woken up 3 times to write data ] malloc(): invalid next size (unsorted) Aborted ``` Backtrace with GDB + debuginfod: ``` malloc(): invalid next size (unsorted) Thread 1 "perf" received signal SIGABRT, Aborted. __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44 Downloading source file /usr/src/debug/glibc/glibc/nptl/pthread_kill.c 44 return INTERNAL_SYSCALL_ERROR_P (ret) ? INTERNAL_SYSCALL_ERRNO (ret) : 0; (gdb) bt #0 __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44 #1 0x00007ffff6ea8eb3 in __pthread_kill_internal (threadid=<optimized out>, signo=6) at pthread_kill.c:78 #2 0x00007ffff6e50a30 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/ raise.c:26 #3 0x00007ffff6e384c3 in __GI_abort () at abort.c:79 #4 0x00007ffff6e39354 in __libc_message_impl (fmt=fmt@entry=0x7ffff6fc22ea "%s\n") at ../sysdeps/posix/libc_fatal.c:132 #5 0x00007ffff6eb3085 in malloc_printerr (str=str@entry=0x7ffff6fc5850 "malloc(): invalid next size (unsorted)") at malloc.c:5772 torvalds#6 0x00007ffff6eb657c in _int_malloc (av=av@entry=0x7ffff6ff6ac0 <main_arena>, bytes=bytes@entry=368) at malloc.c:4081 torvalds#7 0x00007ffff6eb877e in __libc_calloc (n=<optimized out>, elem_size=<optimized out>) at malloc.c:3754 torvalds#8 0x000055555569bdb6 in perf_session.do_write_header () torvalds#9 0x00005555555a373a in __cmd_record.constprop.0 () torvalds#10 0x00005555555a6846 in cmd_record () torvalds#11 0x000055555564db7f in run_builtin () torvalds#12 0x000055555558ed77 in main () ``` Valgrind memcheck: ``` ==45136== Invalid write of size 8 ==45136== at 0x2B38A5: perf_event__synthesize_id_sample (in /usr/bin/perf) ==45136== by 0x157069: __cmd_record.constprop.0 (in /usr/bin/perf) ==45136== by 0x15A845: cmd_record (in /usr/bin/perf) ==45136== by 0x201B7E: run_builtin (in /usr/bin/perf) ==45136== by 0x142D76: main (in /usr/bin/perf) ==45136== Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd ==45136== at 0x4849BF3: calloc (vg_replace_malloc.c:1675) ==45136== by 0x3574AB: zalloc (in /usr/bin/perf) ==45136== by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf) ==45136== by 0x15A845: cmd_record (in /usr/bin/perf) ==45136== by 0x201B7E: run_builtin (in /usr/bin/perf) ==45136== by 0x142D76: main (in /usr/bin/perf) ==45136== ==45136== Syscall param write(buf) points to unaddressable byte(s) ==45136== at 0x575953D: __libc_write (write.c:26) ==45136== by 0x575953D: write (write.c:24) ==45136== by 0x35761F: ion (in /usr/bin/perf) ==45136== by 0x357778: writen (in /usr/bin/perf) ==45136== by 0x1548F7: record__write (in /usr/bin/perf) ==45136== by 0x15708A: __cmd_record.constprop.0 (in /usr/bin/perf) ==45136== by 0x15A845: cmd_record (in /usr/bin/perf) ==45136== by 0x201B7E: run_builtin (in /usr/bin/perf) ==45136== by 0x142D76: main (in /usr/bin/perf) ==45136== Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd ==45136== at 0x4849BF3: calloc (vg_replace_malloc.c:1675) ==45136== by 0x3574AB: zalloc (in /usr/bin/perf) ==45136== by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf) ==45136== by 0x15A845: cmd_record (in /usr/bin/perf) ==45136== by 0x201B7E: run_builtin (in /usr/bin/perf) ==45136== by 0x142D76: main (in /usr/bin/perf) ==45136== ----- Closes: https://lore.kernel.org/linux-perf-users/23879991.0LEYPuXRzz@milian-workstation/ Reported-by: Milian Wolff <milian.wolff@kdab.com> Tested-by: Milian Wolff <milian.wolff@kdab.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: stable@kernel.org # 6.8+ Link: https://lore.kernel.org/lkml/Zl9ksOlHJHnKM70p@x1 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 9d274c1 upstream. We have been seeing crashes on duplicate keys in btrfs_set_item_key_safe(): BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192) ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.c:2620! invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 torvalds#6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs] With the following stack trace: #0 btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4) #1 btrfs_drop_extents (fs/btrfs/file.c:411:4) #2 log_one_extent (fs/btrfs/tree-log.c:4732:9) #3 btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9) #4 btrfs_log_inode (fs/btrfs/tree-log.c:6626:9) #5 btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8) torvalds#6 btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8) torvalds#7 btrfs_sync_file (fs/btrfs/file.c:1933:8) torvalds#8 vfs_fsync_range (fs/sync.c:188:9) torvalds#9 vfs_fsync (fs/sync.c:202:9) torvalds#10 do_fsync (fs/sync.c:212:9) torvalds#11 __do_sys_fdatasync (fs/sync.c:225:9) torvalds#12 __se_sys_fdatasync (fs/sync.c:223:1) torvalds#13 __x64_sys_fdatasync (fs/sync.c:223:1) torvalds#14 do_syscall_x64 (arch/x86/entry/common.c:52:14) torvalds#15 do_syscall_64 (arch/x86/entry/common.c:83:7) torvalds#16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121) So we're logging a changed extent from fsync, which is splitting an extent in the log tree. But this split part already exists in the tree, triggering the BUG(). This is the state of the log tree at the time of the crash, dumped with drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py) to get more details than btrfs_print_leaf() gives us: >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"]) leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610 leaf 33439744 flags 0x100000000000000 fs uuid e5bd3946-400c-4223-8923-190ef1f18677 chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160 generation 7 transid 9 size 8192 nbytes 8473563889606862198 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 204 flags 0x10(PREALLOC) atime 1716417703.220000000 (2024-05-22 15:41:43) ctime 1716417704.983333333 (2024-05-22 15:41:44) mtime 1716417704.983333333 (2024-05-22 15:41:44) otime 17592186044416.000000000 (559444-03-08 01:40:16) item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13 index 195 namelen 3 name: 193 item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37 location key (0 UNKNOWN.0 0) type XATTR transid 7 data_len 1 name_len 6 name: user.a data a item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53 generation 9 type 1 (regular) extent data disk byte 303144960 nr 12288 extent data offset 0 nr 4096 ram 12288 extent compression 0 (none) item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 4096 nr 8192 item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 8192 nr 4096 ... So the real problem happened earlier: notice that items 4 (4k-12k) and 5 (8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and item 5 starts at i_size. Here is the state of the filesystem tree at the time of the crash: >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0)) >>> print_extent_buffer(nodes[0]) leaf 30425088 level 0 items 184 generation 9 owner 5 leaf 30425088 flags 0x100000000000000 fs uuid e5bd3946-400c-4223-8923-190ef1f18677 chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da ... item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160 generation 7 transid 7 size 4096 nbytes 12288 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 6 flags 0x10(PREALLOC) atime 1716417703.220000000 (2024-05-22 15:41:43) ctime 1716417703.220000000 (2024-05-22 15:41:43) mtime 1716417703.220000000 (2024-05-22 15:41:43) otime 1716417703.220000000 (2024-05-22 15:41:43) item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13 index 195 namelen 3 name: 193 item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37 location key (0 UNKNOWN.0 0) type XATTR transid 7 data_len 1 name_len 6 name: user.a data a item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53 generation 9 type 1 (regular) extent data disk byte 303144960 nr 12288 extent data offset 0 nr 8192 ram 12288 extent compression 0 (none) item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 8192 nr 4096 Item 5 in the log tree corresponds to item 183 in the filesystem tree, but nothing matches item 4. Furthermore, item 183 is the last item in the leaf. btrfs_log_prealloc_extents() is responsible for logging prealloc extents beyond i_size. It first truncates any previously logged prealloc extents that start beyond i_size. Then, it walks the filesystem tree and copies the prealloc extent items to the log tree. If it hits the end of a leaf, then it calls btrfs_next_leaf(), which unlocks the tree and does another search. However, while the filesystem tree is unlocked, an ordered extent completion may modify the tree. In particular, it may insert an extent item that overlaps with an extent item that was already copied to the log tree. This may manifest in several ways depending on the exact scenario, including an EEXIST error that is silently translated to a full sync, overlapping items in the log tree, or this crash. This particular crash is triggered by the following sequence of events: - Initially, the file has i_size=4k, a regular extent from 0-4k, and a prealloc extent beyond i_size from 4k-12k. The prealloc extent item is the last item in its B-tree leaf. - The file is fsync'd, which copies its inode item and both extent items to the log tree. - An xattr is set on the file, which sets the BTRFS_INODE_COPY_EVERYTHING flag. - The range 4k-8k in the file is written using direct I/O. i_size is extended to 8k, but the ordered extent is still in flight. - The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this calls copy_inode_items_to_log(), which calls btrfs_log_prealloc_extents(). - btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the filesystem tree. Since it starts before i_size, it skips it. Since it is the last item in its B-tree leaf, it calls btrfs_next_leaf(). - btrfs_next_leaf() unlocks the path. - The ordered extent completion runs, which converts the 4k-8k part of the prealloc extent to written and inserts the remaining prealloc part from 8k-12k. - btrfs_next_leaf() does a search and finds the new prealloc extent 8k-12k. - btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into the log tree. Note that it overlaps with the 4k-12k prealloc extent that was copied to the log tree by the first fsync. - fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k extent that was written. - This tries to drop the range 4k-8k in the log tree, which requires adjusting the start of the 4k-12k prealloc extent in the log tree to 8k. - btrfs_set_item_key_safe() sees that there is already an extent starting at 8k in the log tree and calls BUG(). Fix this by detecting when we're about to insert an overlapping file extent item in the log tree and truncating the part that would overlap. CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 fixes insufficient sanitization of netlink attributes for the inner expression which can trigger nul-pointer dereference, from Davide Ornaghi. Patch #2 address a report that there is a race condition between namespace cleanup and the garbage collection of the list:set type. This patch resolves this issue with other minor issues as well, from Jozsef Kadlecsik. Patch #3 ip6_route_me_harder() ignores flowlabel/dsfield when ip dscp has been mangled, this unbreaks ip6 dscp set $v, from Florian Westphal. All of these patches address issues that are present in several releases. * tag 'nf-24-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: Use flowlabel flow key when re-routing mangled packets netfilter: ipset: Fix race between namespace cleanup and gc in the list:set type netfilter: nft_inner: validate mandatory meta and payload ==================== Link: https://lore.kernel.org/r/20240611220323.413713-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Nikolay Aleksandrov says: ==================== net: bridge: mst: fix suspicious rcu usage warning This set fixes a suspicious RCU usage warning triggered by syzbot[1] in the bridge's MST code. After I converted br_mst_set_state to RCU, I forgot to update the vlan group dereference helper. Fix it by using the proper helper, in order to do that we need to pass the vlan group which is already obtained correctly by the callers for their respective context. Patch 01 is a requirement for the fix in patch 02. Note I did consider rcu_dereference_rtnl() but the churn is much bigger and in every part of the bridge. We can do that as a cleanup in net-next. [1] https://syzkaller.appspot.com/bug?extid=9bbe2de1bc9d470eb5fe ============================= WARNING: suspicious RCU usage 6.10.0-rc2-syzkaller-00235-g8a92980606e3 #0 Not tainted ----------------------------- net/bridge/br_private.h:1599 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 4 locks held by syz-executor.1/5374: #0: ffff888022d50b18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:144 [inline] #0: ffff888022d50b18 (&mm->mmap_lock){++++}-{3:3}, at: __mm_populate+0x1b0/0x460 mm/gup.c:2111 #1: ffffc90000a18c00 ((&p->forward_delay_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x650 kernel/time/timer.c:1789 #2: ffff88805fb2ccb8 (&br->lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #2: ffff88805fb2ccb8 (&br->lock){+.-.}-{2:2}, at: br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86 #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: br_mst_set_state+0x171/0x7a0 net/bridge/br_mst.c:105 stack backtrace: CPU: 1 PID: 5374 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00235-g8a92980606e3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712 nbp_vlan_group net/bridge/br_private.h:1599 [inline] br_mst_set_state+0x29e/0x7a0 net/bridge/br_mst.c:106 br_set_state+0x28a/0x7b0 net/bridge/br_stp.c:47 br_forward_delay_timer_expired+0x176/0x440 net/bridge/br_stp_timer.c:88 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2417 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428 run_timer_base kernel/time/timer.c:2437 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 </IRQ> <TASK> ==================== Link: https://lore.kernel.org/r/20240609103654.914987-1-razor@blackwall.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The syzbot fuzzer found that the interrupt-URB completion callback in the cdc-wdm driver was taking too long, and the driver's immediate resubmission of interrupt URBs with -EPROTO status combined with the dummy-hcd emulation to cause a CPU lockup: cdc_wdm 1-1:1.0: nonzero urb status received: -71 cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625] CPU#0 Utilization every 4s during lockup: #1: 98% system, 0% softirq, 3% hardirq, 0% idle #2: 98% system, 0% softirq, 3% hardirq, 0% idle #3: 98% system, 0% softirq, 3% hardirq, 0% idle #4: 98% system, 0% softirq, 3% hardirq, 0% idle #5: 98% system, 1% softirq, 3% hardirq, 0% idle Modules linked in: irq event stamp: 73096 hardirqs last enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline] hardirqs last enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994 hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline] hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551 softirqs last enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline] softirqs last enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582 softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588 CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G W 6.10.0-rc2-syzkaller-g8867bbd4a056 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Testing showed that the problem did not occur if the two error messages -- the first two lines above -- were removed; apparently adding material to the kernel log takes a surprisingly large amount of time. In any case, the best approach for preventing these lockups and to avoid spamming the log with thousands of error messages per second is to ratelimit the two dev_err() calls. Therefore we replace them with dev_err_ratelimited(). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Suggested-by: Greg KH <gregkh@linuxfoundation.org> Reported-and-tested-by: syzbot+5f996b83575ef4058638@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-usb/00000000000073d54b061a6a1c65@google.com/ Reported-and-tested-by: syzbot+1b2abad17596ad03dcff@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-usb/000000000000f45085061aa9b37e@google.com/ Fixes: 9908a32 ("USB: remove err() macro from usb class drivers") Link: https://lore.kernel.org/linux-usb/40dfa45b-5f21-4eef-a8c1-51a2f320e267@rowland.harvard.edu/ Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/29855215-52f5-4385-b058-91f42c2bee18@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 22f0081 upstream. The syzbot fuzzer found that the interrupt-URB completion callback in the cdc-wdm driver was taking too long, and the driver's immediate resubmission of interrupt URBs with -EPROTO status combined with the dummy-hcd emulation to cause a CPU lockup: cdc_wdm 1-1:1.0: nonzero urb status received: -71 cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625] CPU#0 Utilization every 4s during lockup: #1: 98% system, 0% softirq, 3% hardirq, 0% idle #2: 98% system, 0% softirq, 3% hardirq, 0% idle #3: 98% system, 0% softirq, 3% hardirq, 0% idle #4: 98% system, 0% softirq, 3% hardirq, 0% idle #5: 98% system, 1% softirq, 3% hardirq, 0% idle Modules linked in: irq event stamp: 73096 hardirqs last enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline] hardirqs last enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994 hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline] hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551 softirqs last enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline] softirqs last enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582 softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588 CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G W 6.10.0-rc2-syzkaller-g8867bbd4a056 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Testing showed that the problem did not occur if the two error messages -- the first two lines above -- were removed; apparently adding material to the kernel log takes a surprisingly large amount of time. In any case, the best approach for preventing these lockups and to avoid spamming the log with thousands of error messages per second is to ratelimit the two dev_err() calls. Therefore we replace them with dev_err_ratelimited(). Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Suggested-by: Greg KH <gregkh@linuxfoundation.org> Reported-and-tested-by: syzbot+5f996b83575ef4058638@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-usb/00000000000073d54b061a6a1c65@google.com/ Reported-and-tested-by: syzbot+1b2abad17596ad03dcff@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-usb/000000000000f45085061aa9b37e@google.com/ Fixes: 9908a32 ("USB: remove err() macro from usb class drivers") Link: https://lore.kernel.org/linux-usb/40dfa45b-5f21-4eef-a8c1-51a2f320e267@rowland.harvard.edu/ Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/29855215-52f5-4385-b058-91f42c2bee18@rowland.harvard.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 fixes the suspicious RCU usage warning that resulted from the recent fix for the race between namespace cleanup and gc in ipset left out checking the pernet exit phase when calling rcu_dereference_protected(), from Jozsef Kadlecsik. Patch #2 fixes incorrect input and output netdevice in SRv6 prerouting hooks, from Jianguo Wu. Patch #3 moves nf_hooks_lwtunnel sysctl toggle to the netfilter core. The connection tracking system is loaded on-demand, this ensures availability of this knob regardless. Patch #4-#5 adds selftests for SRv6 netfilter hooks also from Jianguo Wu. netfilter pull request 24-06-19 * tag 'nf-24-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: selftests: add selftest for the SRv6 End.DX6 behavior with netfilter selftests: add selftest for the SRv6 End.DX4 behavior with netfilter netfilter: move the sysctl nf_hooks_lwtunnel into the netfilter core seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 behaviors netfilter: ipset: Fix suspicious rcu_dereference_protected() ==================== Link: https://lore.kernel.org/r/20240619170537.2846-1-pablo@netfilter.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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[ Upstream commit 668c040 ] When the torture_type is set srcu or srcud and cb_barrier is non-zero, running the rcutorture test will trigger the following warning: [ 163.910989][ C1] BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 [ 163.910994][ C1] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/1 [ 163.910999][ C1] preempt_count: 10001, expected: 0 [ 163.911002][ C1] RCU nest depth: 0, expected: 0 [ 163.911005][ C1] INFO: lockdep is turned off. [ 163.911007][ C1] irq event stamp: 30964 [ 163.911010][ C1] hardirqs last enabled at (30963): [<ffffffffabc7df52>] do_idle+0x362/0x500 [ 163.911018][ C1] hardirqs last disabled at (30964): [<ffffffffae616eff>] sysvec_call_function_single+0xf/0xd0 [ 163.911025][ C1] softirqs last enabled at (0): [<ffffffffabb6475f>] copy_process+0x16ff/0x6580 [ 163.911033][ C1] softirqs last disabled at (0): [<0000000000000000>] 0x0 [ 163.911038][ C1] Preemption disabled at: [ 163.911039][ C1] [<ffffffffacf1964b>] stack_depot_save_flags+0x24b/0x6c0 [ 163.911063][ C1] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G W 6.8.0-rc4-rt4-yocto-preempt-rt+ #3 1e39aa9a737dd024a3275c4f835a872f673a7d3a [ 163.911071][ C1] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [ 163.911075][ C1] Call Trace: [ 163.911078][ C1] <IRQ> [ 163.911080][ C1] dump_stack_lvl+0x88/0xd0 [ 163.911089][ C1] dump_stack+0x10/0x20 [ 163.911095][ C1] __might_resched+0x36f/0x530 [ 163.911105][ C1] rt_spin_lock+0x82/0x1c0 [ 163.911112][ C1] spin_lock_irqsave_ssp_contention+0xb8/0x100 [ 163.911121][ C1] srcu_gp_start_if_needed+0x782/0xf00 [ 163.911128][ C1] ? _raw_spin_unlock_irqrestore+0x46/0x70 [ 163.911136][ C1] ? debug_object_active_state+0x336/0x470 [ 163.911148][ C1] ? __pfx_srcu_gp_start_if_needed+0x10/0x10 [ 163.911156][ C1] ? __pfx_lock_release+0x10/0x10 [ 163.911165][ C1] ? __pfx_rcu_torture_barrier_cbf+0x10/0x10 [ 163.911188][ C1] __call_srcu+0x9f/0xe0 [ 163.911196][ C1] call_srcu+0x13/0x20 [ 163.911201][ C1] srcu_torture_call+0x1b/0x30 [ 163.911224][ C1] rcu_torture_barrier1cb+0x4a/0x60 [ 163.911247][ C1] __flush_smp_call_function_queue+0x267/0xca0 [ 163.911256][ C1] ? __pfx_rcu_torture_barrier1cb+0x10/0x10 [ 163.911281][ C1] generic_smp_call_function_single_interrupt+0x13/0x20 [ 163.911288][ C1] __sysvec_call_function_single+0x7d/0x280 [ 163.911295][ C1] sysvec_call_function_single+0x93/0xd0 [ 163.911302][ C1] </IRQ> [ 163.911304][ C1] <TASK> [ 163.911308][ C1] asm_sysvec_call_function_single+0x1b/0x20 [ 163.911313][ C1] RIP: 0010:default_idle+0x17/0x20 [ 163.911326][ C1] RSP: 0018:ffff888001997dc8 EFLAGS: 00000246 [ 163.911333][ C1] RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffffae618b51 [ 163.911337][ C1] RDX: 0000000000000000 RSI: ffffffffaea80920 RDI: ffffffffaec2de80 [ 163.911342][ C1] RBP: ffff888001997dc8 R08: 0000000000000001 R09: ffffed100d740cad [ 163.911346][ C1] R10: ffffed100d740cac R11: ffff88806ba06563 R12: 0000000000000001 [ 163.911350][ C1] R13: ffffffffafe460c0 R14: ffffffffafe460c0 R15: 0000000000000000 [ 163.911358][ C1] ? ct_kernel_exit.constprop.3+0x121/0x160 [ 163.911369][ C1] ? lockdep_hardirqs_on+0xc4/0x150 [ 163.911376][ C1] arch_cpu_idle+0x9/0x10 [ 163.911383][ C1] default_idle_call+0x7a/0xb0 [ 163.911390][ C1] do_idle+0x362/0x500 [ 163.911398][ C1] ? __pfx_do_idle+0x10/0x10 [ 163.911404][ C1] ? complete_with_flags+0x8b/0xb0 [ 163.911416][ C1] cpu_startup_entry+0x58/0x70 [ 163.911423][ C1] start_secondary+0x221/0x280 [ 163.911430][ C1] ? __pfx_start_secondary+0x10/0x10 [ 163.911440][ C1] secondary_startup_64_no_verify+0x17f/0x18b [ 163.911455][ C1] </TASK> This commit therefore use smp_call_on_cpu() instead of smp_call_function_single(), make rcu_torture_barrier1cb() invoked happens on task-context. Signed-off-by: Zqiang <qiang.zhang1211@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit f1e197a ] trace_drop_common() is called with preemption disabled, and it acquires a spin_lock. This is problematic for RT kernels because spin_locks are sleeping locks in this configuration, which causes the following splat: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 449, name: rcuc/47 preempt_count: 1, expected: 0 RCU nest depth: 2, expected: 2 5 locks held by rcuc/47/449: #0: ff1100086ec30a60 ((softirq_ctrl.lock)){+.+.}-{2:2}, at: __local_bh_disable_ip+0x105/0x210 #1: ffffffffb394a280 (rcu_read_lock){....}-{1:2}, at: rt_spin_lock+0xbf/0x130 #2: ffffffffb394a280 (rcu_read_lock){....}-{1:2}, at: __local_bh_disable_ip+0x11c/0x210 #3: ffffffffb394a160 (rcu_callback){....}-{0:0}, at: rcu_do_batch+0x360/0xc70 #4: ff1100086ee07520 (&data->lock){+.+.}-{2:2}, at: trace_drop_common.constprop.0+0xb5/0x290 irq event stamp: 139909 hardirqs last enabled at (139908): [<ffffffffb1df2b33>] _raw_spin_unlock_irqrestore+0x63/0x80 hardirqs last disabled at (139909): [<ffffffffb19bd03d>] trace_drop_common.constprop.0+0x26d/0x290 softirqs last enabled at (139892): [<ffffffffb07a1083>] __local_bh_enable_ip+0x103/0x170 softirqs last disabled at (139898): [<ffffffffb0909b33>] rcu_cpu_kthread+0x93/0x1f0 Preemption disabled at: [<ffffffffb1de786b>] rt_mutex_slowunlock+0xab/0x2e0 CPU: 47 PID: 449 Comm: rcuc/47 Not tainted 6.9.0-rc2-rt1+ torvalds#7 Hardware name: Dell Inc. PowerEdge R650/0Y2G81, BIOS 1.6.5 04/15/2022 Call Trace: <TASK> dump_stack_lvl+0x8c/0xd0 dump_stack+0x14/0x20 __might_resched+0x21e/0x2f0 rt_spin_lock+0x5e/0x130 ? trace_drop_common.constprop.0+0xb5/0x290 ? skb_queue_purge_reason.part.0+0x1bf/0x230 trace_drop_common.constprop.0+0xb5/0x290 ? preempt_count_sub+0x1c/0xd0 ? _raw_spin_unlock_irqrestore+0x4a/0x80 ? __pfx_trace_drop_common.constprop.0+0x10/0x10 ? rt_mutex_slowunlock+0x26a/0x2e0 ? skb_queue_purge_reason.part.0+0x1bf/0x230 ? __pfx_rt_mutex_slowunlock+0x10/0x10 ? skb_queue_purge_reason.part.0+0x1bf/0x230 trace_kfree_skb_hit+0x15/0x20 trace_kfree_skb+0xe9/0x150 kfree_skb_reason+0x7b/0x110 skb_queue_purge_reason.part.0+0x1bf/0x230 ? __pfx_skb_queue_purge_reason.part.0+0x10/0x10 ? mark_lock.part.0+0x8a/0x520 ... trace_drop_common() also disables interrupts, but this is a minor issue because we could easily replace it with a local_lock. Replace the spin_lock with raw_spin_lock to avoid sleeping in atomic context. Signed-off-by: Wander Lairson Costa <wander@redhat.com> Reported-by: Hu Chunyu <chuhu@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit af0cb3f ] Xiumei and Christoph reported the following lockdep splat, complaining of the qdisc root lock being taken twice: ============================================ WARNING: possible recursive locking detected 6.7.0-rc3+ torvalds#598 Not tainted -------------------------------------------- swapper/2/0 is trying to acquire lock: ffff888177190110 (&sch->q.lock){+.-.}-{2:2}, at: __dev_queue_xmit+0x1560/0x2e70 but task is already holding lock: ffff88811995a110 (&sch->q.lock){+.-.}-{2:2}, at: __dev_queue_xmit+0x1560/0x2e70 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&sch->q.lock); lock(&sch->q.lock); *** DEADLOCK *** May be due to missing lock nesting notation 5 locks held by swapper/2/0: #0: ffff888135a09d98 ((&in_dev->mr_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0x11a/0x510 #1: ffffffffaaee5260 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x2c0/0x1ed0 #2: ffffffffaaee5200 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x209/0x2e70 #3: ffff88811995a110 (&sch->q.lock){+.-.}-{2:2}, at: __dev_queue_xmit+0x1560/0x2e70 #4: ffffffffaaee5200 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x209/0x2e70 stack backtrace: CPU: 2 PID: 0 Comm: swapper/2 Not tainted 6.7.0-rc3+ torvalds#598 Hardware name: Red Hat KVM, BIOS 1.13.0-2.module+el8.3.0+7353+9de0a3cc 04/01/2014 Call Trace: <IRQ> dump_stack_lvl+0x4a/0x80 __lock_acquire+0xfdd/0x3150 lock_acquire+0x1ca/0x540 _raw_spin_lock+0x34/0x80 __dev_queue_xmit+0x1560/0x2e70 tcf_mirred_act+0x82e/0x1260 [act_mirred] tcf_action_exec+0x161/0x480 tcf_classify+0x689/0x1170 prio_enqueue+0x316/0x660 [sch_prio] dev_qdisc_enqueue+0x46/0x220 __dev_queue_xmit+0x1615/0x2e70 ip_finish_output2+0x1218/0x1ed0 __ip_finish_output+0x8b3/0x1350 ip_output+0x163/0x4e0 igmp_ifc_timer_expire+0x44b/0x930 call_timer_fn+0x1a2/0x510 run_timer_softirq+0x54d/0x11a0 __do_softirq+0x1b3/0x88f irq_exit_rcu+0x18f/0x1e0 sysvec_apic_timer_interrupt+0x6f/0x90 </IRQ> This happens when TC does a mirred egress redirect from the root qdisc of device A to the root qdisc of device B. As long as these two locks aren't protecting the same qdisc, they can be acquired in chain: add a per-qdisc lockdep key to silence false warnings. This dynamic key should safely replace the static key we have in sch_htb: it was added to allow enqueueing to the device "direct qdisc" while still holding the qdisc root lock. v2: don't use static keys anymore in HTB direct qdiscs (thanks Eric Dumazet) CC: Maxim Mikityanskiy <maxim@isovalent.com> CC: Xiumei Mu <xmu@redhat.com> Reported-by: Christoph Paasch <cpaasch@apple.com> Closes: multipath-tcp/mptcp_net-next#451 Signed-off-by: Davide Caratti <dcaratti@redhat.com> Link: https://lore.kernel.org/r/7dc06d6158f72053cf877a82e2a7a5bd23692faa.1713448007.git.dcaratti@redhat.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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Jun 27, 2024
[ Upstream commit f6944d4 ] Lockdep reports the below circular locking dependency issue. The mmap_lock acquisition while holding pci_bus_sem is due to the use of copy_to_user() from within a pci_walk_bus() callback. Building the devices array directly into the user buffer is only for convenience. Instead we can allocate a local buffer for the array, bounded by the number of devices on the bus/slot, fill the device information into this local buffer, then copy it into the user buffer outside the bus walk callback. ====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc5+ torvalds#39 Not tainted ------------------------------------------------------ CPU 0/KVM/4113 is trying to acquire lock: ffff99a609ee18a8 (&vdev->vma_lock){+.+.}-{4:4}, at: vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core] but task is already holding lock: ffff99a243a052a0 (&mm->mmap_lock){++++}-{4:4}, at: vaddr_get_pfns+0x3f/0x170 [vfio_iommu_type1] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&mm->mmap_lock){++++}-{4:4}: __lock_acquire+0x4e4/0xb90 lock_acquire+0xbc/0x2d0 __might_fault+0x5c/0x80 _copy_to_user+0x1e/0x60 vfio_pci_fill_devs+0x9f/0x130 [vfio_pci_core] vfio_pci_walk_wrapper+0x45/0x60 [vfio_pci_core] __pci_walk_bus+0x6b/0xb0 vfio_pci_ioctl_get_pci_hot_reset_info+0x10b/0x1d0 [vfio_pci_core] vfio_pci_core_ioctl+0x1cb/0x400 [vfio_pci_core] vfio_device_fops_unl_ioctl+0x7e/0x140 [vfio] __x64_sys_ioctl+0x8a/0xc0 do_syscall_64+0x8d/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #2 (pci_bus_sem){++++}-{4:4}: __lock_acquire+0x4e4/0xb90 lock_acquire+0xbc/0x2d0 down_read+0x3e/0x160 pci_bridge_wait_for_secondary_bus.part.0+0x33/0x2d0 pci_reset_bus+0xdd/0x160 vfio_pci_dev_set_hot_reset+0x256/0x270 [vfio_pci_core] vfio_pci_ioctl_pci_hot_reset_groups+0x1a3/0x280 [vfio_pci_core] vfio_pci_core_ioctl+0x3b5/0x400 [vfio_pci_core] vfio_device_fops_unl_ioctl+0x7e/0x140 [vfio] __x64_sys_ioctl+0x8a/0xc0 do_syscall_64+0x8d/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (&vdev->memory_lock){+.+.}-{4:4}: __lock_acquire+0x4e4/0xb90 lock_acquire+0xbc/0x2d0 down_write+0x3b/0xc0 vfio_pci_zap_and_down_write_memory_lock+0x1c/0x30 [vfio_pci_core] vfio_basic_config_write+0x281/0x340 [vfio_pci_core] vfio_config_do_rw+0x1fa/0x300 [vfio_pci_core] vfio_pci_config_rw+0x75/0xe50 [vfio_pci_core] vfio_pci_rw+0xea/0x1a0 [vfio_pci_core] vfs_write+0xea/0x520 __x64_sys_pwrite64+0x90/0xc0 do_syscall_64+0x8d/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #0 (&vdev->vma_lock){+.+.}-{4:4}: check_prev_add+0xeb/0xcc0 validate_chain+0x465/0x530 __lock_acquire+0x4e4/0xb90 lock_acquire+0xbc/0x2d0 __mutex_lock+0x97/0xde0 vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core] __do_fault+0x31/0x160 do_pte_missing+0x65/0x3b0 __handle_mm_fault+0x303/0x720 handle_mm_fault+0x10f/0x460 fixup_user_fault+0x7f/0x1f0 follow_fault_pfn+0x66/0x1c0 [vfio_iommu_type1] vaddr_get_pfns+0xf2/0x170 [vfio_iommu_type1] vfio_pin_pages_remote+0x348/0x4e0 [vfio_iommu_type1] vfio_pin_map_dma+0xd2/0x330 [vfio_iommu_type1] vfio_dma_do_map+0x2c0/0x440 [vfio_iommu_type1] vfio_iommu_type1_ioctl+0xc5/0x1d0 [vfio_iommu_type1] __x64_sys_ioctl+0x8a/0xc0 do_syscall_64+0x8d/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: &vdev->vma_lock --> pci_bus_sem --> &mm->mmap_lock Possible unsafe locking scenario: block dm-0: the capability attribute has been deprecated. CPU0 CPU1 ---- ---- rlock(&mm->mmap_lock); lock(pci_bus_sem); lock(&mm->mmap_lock); lock(&vdev->vma_lock); *** DEADLOCK *** 2 locks held by CPU 0/KVM/4113: #0: ffff99a25f294888 (&iommu->lock#2){+.+.}-{4:4}, at: vfio_dma_do_map+0x60/0x440 [vfio_iommu_type1] #1: ffff99a243a052a0 (&mm->mmap_lock){++++}-{4:4}, at: vaddr_get_pfns+0x3f/0x170 [vfio_iommu_type1] stack backtrace: CPU: 1 PID: 4113 Comm: CPU 0/KVM Not tainted 6.9.0-rc5+ torvalds#39 Hardware name: Dell Inc. PowerEdge T640/04WYPY, BIOS 2.15.1 06/16/2022 Call Trace: <TASK> dump_stack_lvl+0x64/0xa0 check_noncircular+0x131/0x150 check_prev_add+0xeb/0xcc0 ? add_chain_cache+0x10a/0x2f0 ? __lock_acquire+0x4e4/0xb90 validate_chain+0x465/0x530 __lock_acquire+0x4e4/0xb90 lock_acquire+0xbc/0x2d0 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core] ? lock_is_held_type+0x9a/0x110 __mutex_lock+0x97/0xde0 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core] ? lock_acquire+0xbc/0x2d0 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core] ? find_held_lock+0x2b/0x80 ? vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core] vfio_pci_mmap_fault+0x35/0x1a0 [vfio_pci_core] __do_fault+0x31/0x160 do_pte_missing+0x65/0x3b0 __handle_mm_fault+0x303/0x720 handle_mm_fault+0x10f/0x460 fixup_user_fault+0x7f/0x1f0 follow_fault_pfn+0x66/0x1c0 [vfio_iommu_type1] vaddr_get_pfns+0xf2/0x170 [vfio_iommu_type1] vfio_pin_pages_remote+0x348/0x4e0 [vfio_iommu_type1] vfio_pin_map_dma+0xd2/0x330 [vfio_iommu_type1] vfio_dma_do_map+0x2c0/0x440 [vfio_iommu_type1] vfio_iommu_type1_ioctl+0xc5/0x1d0 [vfio_iommu_type1] __x64_sys_ioctl+0x8a/0xc0 do_syscall_64+0x8d/0x170 ? rcu_core+0x8d/0x250 ? __lock_release+0x5e/0x160 ? rcu_core+0x8d/0x250 ? lock_release+0x5f/0x120 ? sched_clock+0xc/0x30 ? sched_clock_cpu+0xb/0x190 ? irqtime_account_irq+0x40/0xc0 ? __local_bh_enable+0x54/0x60 ? __do_softirq+0x315/0x3ca ? lockdep_hardirqs_on_prepare.part.0+0x97/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f8300d0357b Code: ff ff ff 85 c0 79 9b 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 75 68 0f 00 f7 d8 64 89 01 48 RSP: 002b:00007f82ef3fb948 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8300d0357b RDX: 00007f82ef3fb990 RSI: 0000000000003b71 RDI: 0000000000000023 RBP: 00007f82ef3fb9c0 R08: 0000000000000000 R09: 0000561b7e0bcac2 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000200000000 R14: 0000381800000000 R15: 0000000000000000 </TASK> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20240503143138.3562116-1-alex.williamson@redhat.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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…play
During inode logging (and log replay too), we are holding a transaction
handle and we often need to call btrfs_iget(), which will read an inode
from its subvolume btree if it's not loaded in memory and that results in
allocating an inode with GFP_KERNEL semantics at the btrfs_alloc_inode()
callback - and this may recurse into the filesystem in case we are under
memory pressure and attempt to commit the current transaction, resulting
in a deadlock since the logging (or log replay) task is holding a
transaction handle open.
Syzbot reported this with the following stack traces:
WARNING: possible circular locking dependency detected
6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0 Not tainted
------------------------------------------------------
syz-executor.1/9919 is trying to acquire lock:
ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline]
ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline]
ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline]
ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
but task is already holding lock:
ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (&ei->log_mutex){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:608 [inline]
__mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481
btrfs_log_inode_parent+0x8cb/0x2a90 fs/btrfs/tree-log.c:7079
btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
vfs_fsync_range+0x141/0x230 fs/sync.c:188
generic_write_sync include/linux/fs.h:2794 [inline]
btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0x6b6/0x1140 fs/read_write.c:590
ksys_write+0x12f/0x260 fs/read_write.c:643
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
-> #2 (btrfs_trans_num_extwriters){++++}-{0:0}:
join_transaction+0x164/0xf40 fs/btrfs/transaction.c:315
start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700
btrfs_commit_super+0xa1/0x110 fs/btrfs/disk-io.c:4170
close_ctree+0xcb0/0xf90 fs/btrfs/disk-io.c:4324
generic_shutdown_super+0x159/0x3d0 fs/super.c:642
kill_anon_super+0x3a/0x60 fs/super.c:1226
btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2096
deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
deactivate_super+0xde/0x100 fs/super.c:506
cleanup_mnt+0x222/0x450 fs/namespace.c:1267
task_work_run+0x14e/0x250 kernel/task_work.c:180
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218
__do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
-> #1 (btrfs_trans_num_writers){++++}-{0:0}:
__lock_release kernel/locking/lockdep.c:5468 [inline]
lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774
percpu_up_read include/linux/percpu-rwsem.h:99 [inline]
__sb_end_write include/linux/fs.h:1650 [inline]
sb_end_intwrite include/linux/fs.h:1767 [inline]
__btrfs_end_transaction+0x5ca/0x920 fs/btrfs/transaction.c:1071
btrfs_commit_inode_delayed_inode+0x228/0x330 fs/btrfs/delayed-inode.c:1301
btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291
evict+0x2ed/0x6c0 fs/inode.c:667
iput_final fs/inode.c:1741 [inline]
iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
iput+0x5c/0x80 fs/inode.c:1757
dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
__dentry_kill+0x1d0/0x600 fs/dcache.c:603
dput.part.0+0x4b1/0x9b0 fs/dcache.c:845
dput+0x1f/0x30 fs/dcache.c:835
ovl_stack_put+0x60/0x90 fs/overlayfs/util.c:132
ovl_destroy_inode+0xc6/0x190 fs/overlayfs/super.c:182
destroy_inode+0xc4/0x1b0 fs/inode.c:311
iput_final fs/inode.c:1741 [inline]
iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
iput+0x5c/0x80 fs/inode.c:1757
dentry_unlink_inode+0x295/0x480 fs/dcache.c:400
__dentry_kill+0x1d0/0x600 fs/dcache.c:603
shrink_kill fs/dcache.c:1048 [inline]
shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075
prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156
super_cache_scan+0x32a/0x550 fs/super.c:221
do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
shrink_slab_memcg mm/shrinker.c:548 [inline]
shrink_slab+0xa87/0x1310 mm/shrinker.c:626
shrink_one+0x493/0x7c0 mm/vmscan.c:4790
shrink_many mm/vmscan.c:4851 [inline]
lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
shrink_node mm/vmscan.c:5910 [inline]
kswapd_shrink_node mm/vmscan.c:6720 [inline]
balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #0 (fs_reclaim){+.+.}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
__fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
might_alloc include/linux/sched/mm.h:334 [inline]
slab_pre_alloc_hook mm/slub.c:3891 [inline]
slab_alloc_node mm/slub.c:3981 [inline]
kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
alloc_inode+0x5d/0x230 fs/inode.c:261
iget5_locked fs/inode.c:1235 [inline]
iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
vfs_fsync_range+0x141/0x230 fs/sync.c:188
generic_write_sync include/linux/fs.h:2794 [inline]
btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
vfs_writev+0x36f/0xde0 fs/read_write.c:971
do_pwritev+0x1b2/0x260 fs/read_write.c:1072
__do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
__se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
__ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
other info that might help us debug this:
Chain exists of:
fs_reclaim --> btrfs_trans_num_extwriters --> &ei->log_mutex
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ei->log_mutex);
lock(btrfs_trans_num_extwriters);
lock(&ei->log_mutex);
lock(fs_reclaim);
*** DEADLOCK ***
7 locks held by syz-executor.1/9919:
#0: ffff88802be20420 (sb_writers#23){.+.+}-{0:0}, at: do_pwritev+0x1b2/0x260 fs/read_write.c:1072
#1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline]
#1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: btrfs_inode_lock+0xc8/0x110 fs/btrfs/inode.c:385
#2: ffff888065c0f778 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_inode_lock+0xee/0x110 fs/btrfs/inode.c:388
#3: ffff88802be20610 (sb_internal#4){.+.+}-{0:0}, at: btrfs_sync_file+0x95b/0xe10 fs/btrfs/file.c:1952
#4: ffff8880546323f0 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
#5: ffff888054632418 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290
torvalds#6: ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481
stack backtrace:
CPU: 2 PID: 9919 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
__fs_reclaim_acquire mm/page_alloc.c:3801 [inline]
fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815
might_alloc include/linux/sched/mm.h:334 [inline]
slab_pre_alloc_hook mm/slub.c:3891 [inline]
slab_alloc_node mm/slub.c:3981 [inline]
kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020
btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
alloc_inode+0x5d/0x230 fs/inode.c:261
iget5_locked fs/inode.c:1235 [inline]
iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline]
copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928
btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592
log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline]
btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718
btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline]
btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141
btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180
btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959
vfs_fsync_range+0x141/0x230 fs/sync.c:188
generic_write_sync include/linux/fs.h:2794 [inline]
btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705
do_iter_readv_writev+0x504/0x780 fs/read_write.c:741
vfs_writev+0x36f/0xde0 fs/read_write.c:971
do_pwritev+0x1b2/0x260 fs/read_write.c:1072
__do_compat_sys_pwritev2 fs/read_write.c:1218 [inline]
__se_compat_sys_pwritev2 fs/read_write.c:1210 [inline]
__ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7334579
Code: b8 01 10 06 03 (...)
RSP: 002b:00000000f5f265ac EFLAGS: 00000292 ORIG_RAX: 000000000000017b
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000200002c0
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Fix this by ensuring we are under a NOFS scope whenever we call
btrfs_iget() during inode logging and log replay.
Reported-by: syzbot+8576cfa84070dce4d59b@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/000000000000274a3a061abbd928@google.com/
Fixes: 712e36c ("btrfs: use GFP_KERNEL in btrfs_alloc_inode")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
ptr1337
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The code in ocfs2_dio_end_io_write() estimates number of necessary transaction credits using ocfs2_calc_extend_credits(). This however does not take into account that the IO could be arbitrarily large and can contain arbitrary number of extents. Extent tree manipulations do often extend the current transaction but not in all of the cases. For example if we have only single block extents in the tree, ocfs2_mark_extent_written() will end up calling ocfs2_replace_extent_rec() all the time and we will never extend the current transaction and eventually exhaust all the transaction credits if the IO contains many single block extents. Once that happens a WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to this error. This was actually triggered by one of our customers on a heavily fragmented OCFS2 filesystem. To fix the issue make sure the transaction always has enough credits for one extent insert before each call of ocfs2_mark_extent_written(). Heming Zhao said: ------ PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error" PID: xxx TASK: xxxx CPU: 5 COMMAND: "SubmitThread-CA" #0 machine_kexec at ffffffff8c069932 #1 __crash_kexec at ffffffff8c1338fa #2 panic at ffffffff8c1d69b9 #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2] #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2] #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2] torvalds#6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2] torvalds#7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2] torvalds#8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2] torvalds#9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2] torvalds#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2] torvalds#11 dio_complete at ffffffff8c2b9fa7 torvalds#12 do_blockdev_direct_IO at ffffffff8c2bc09f torvalds#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2] torvalds#14 generic_file_direct_write at ffffffff8c1dcf14 torvalds#15 __generic_file_write_iter at ffffffff8c1dd07b torvalds#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2] torvalds#17 aio_write at ffffffff8c2cc72e torvalds#18 kmem_cache_alloc at ffffffff8c248dde torvalds#19 do_io_submit at ffffffff8c2ccada torvalds#20 do_syscall_64 at ffffffff8c004984 torvalds#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io") Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by: Heming Zhao <heming.zhao@suse.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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…play [ Upstream commit d182575 ] During inode logging (and log replay too), we are holding a transaction handle and we often need to call btrfs_iget(), which will read an inode from its subvolume btree if it's not loaded in memory and that results in allocating an inode with GFP_KERNEL semantics at the btrfs_alloc_inode() callback - and this may recurse into the filesystem in case we are under memory pressure and attempt to commit the current transaction, resulting in a deadlock since the logging (or log replay) task is holding a transaction handle open. Syzbot reported this with the following stack traces: WARNING: possible circular locking dependency detected 6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0 Not tainted ------------------------------------------------------ syz-executor.1/9919 is trying to acquire lock: ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline] ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline] ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline] ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020 but task is already holding lock: ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ei->log_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481 btrfs_log_inode_parent+0x8cb/0x2a90 fs/btrfs/tree-log.c:7079 btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180 btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959 vfs_fsync_range+0x141/0x230 fs/sync.c:188 generic_write_sync include/linux/fs.h:2794 [inline] btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705 new_sync_write fs/read_write.c:497 [inline] vfs_write+0x6b6/0x1140 fs/read_write.c:590 ksys_write+0x12f/0x260 fs/read_write.c:643 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}: join_transaction+0x164/0xf40 fs/btrfs/transaction.c:315 start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700 btrfs_commit_super+0xa1/0x110 fs/btrfs/disk-io.c:4170 close_ctree+0xcb0/0xf90 fs/btrfs/disk-io.c:4324 generic_shutdown_super+0x159/0x3d0 fs/super.c:642 kill_anon_super+0x3a/0x60 fs/super.c:1226 btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2096 deactivate_locked_super+0xbe/0x1a0 fs/super.c:473 deactivate_super+0xde/0x100 fs/super.c:506 cleanup_mnt+0x222/0x450 fs/namespace.c:1267 task_work_run+0x14e/0x250 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218 __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #1 (btrfs_trans_num_writers){++++}-{0:0}: __lock_release kernel/locking/lockdep.c:5468 [inline] lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774 percpu_up_read include/linux/percpu-rwsem.h:99 [inline] __sb_end_write include/linux/fs.h:1650 [inline] sb_end_intwrite include/linux/fs.h:1767 [inline] __btrfs_end_transaction+0x5ca/0x920 fs/btrfs/transaction.c:1071 btrfs_commit_inode_delayed_inode+0x228/0x330 fs/btrfs/delayed-inode.c:1301 btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291 evict+0x2ed/0x6c0 fs/inode.c:667 iput_final fs/inode.c:1741 [inline] iput.part.0+0x5a8/0x7f0 fs/inode.c:1767 iput+0x5c/0x80 fs/inode.c:1757 dentry_unlink_inode+0x295/0x480 fs/dcache.c:400 __dentry_kill+0x1d0/0x600 fs/dcache.c:603 dput.part.0+0x4b1/0x9b0 fs/dcache.c:845 dput+0x1f/0x30 fs/dcache.c:835 ovl_stack_put+0x60/0x90 fs/overlayfs/util.c:132 ovl_destroy_inode+0xc6/0x190 fs/overlayfs/super.c:182 destroy_inode+0xc4/0x1b0 fs/inode.c:311 iput_final fs/inode.c:1741 [inline] iput.part.0+0x5a8/0x7f0 fs/inode.c:1767 iput+0x5c/0x80 fs/inode.c:1757 dentry_unlink_inode+0x295/0x480 fs/dcache.c:400 __dentry_kill+0x1d0/0x600 fs/dcache.c:603 shrink_kill fs/dcache.c:1048 [inline] shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075 prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156 super_cache_scan+0x32a/0x550 fs/super.c:221 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0xa87/0x1310 mm/shrinker.c:626 shrink_one+0x493/0x7c0 mm/vmscan.c:4790 shrink_many mm/vmscan.c:4851 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951 shrink_node mm/vmscan.c:5910 [inline] kswapd_shrink_node mm/vmscan.c:6720 [inline] balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (fs_reclaim){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3801 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3891 [inline] slab_alloc_node mm/slub.c:3981 [inline] kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020 btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411 alloc_inode+0x5d/0x230 fs/inode.c:261 iget5_locked fs/inode.c:1235 [inline] iget5_locked+0x1c9/0x2c0 fs/inode.c:1228 btrfs_iget_locked fs/btrfs/inode.c:5590 [inline] btrfs_iget_path fs/btrfs/inode.c:5607 [inline] btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636 add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline] copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928 btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592 log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline] btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718 btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline] btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141 btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180 btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959 vfs_fsync_range+0x141/0x230 fs/sync.c:188 generic_write_sync include/linux/fs.h:2794 [inline] btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705 do_iter_readv_writev+0x504/0x780 fs/read_write.c:741 vfs_writev+0x36f/0xde0 fs/read_write.c:971 do_pwritev+0x1b2/0x260 fs/read_write.c:1072 __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline] __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline] __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e other info that might help us debug this: Chain exists of: fs_reclaim --> btrfs_trans_num_extwriters --> &ei->log_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->log_mutex); lock(btrfs_trans_num_extwriters); lock(&ei->log_mutex); lock(fs_reclaim); *** DEADLOCK *** 7 locks held by syz-executor.1/9919: #0: ffff88802be20420 (sb_writers#23){.+.+}-{0:0}, at: do_pwritev+0x1b2/0x260 fs/read_write.c:1072 #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline] #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: btrfs_inode_lock+0xc8/0x110 fs/btrfs/inode.c:385 #2: ffff888065c0f778 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_inode_lock+0xee/0x110 fs/btrfs/inode.c:388 #3: ffff88802be20610 (sb_internal#4){.+.+}-{0:0}, at: btrfs_sync_file+0x95b/0xe10 fs/btrfs/file.c:1952 #4: ffff8880546323f0 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290 #5: ffff888054632418 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290 torvalds#6: ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481 stack backtrace: CPU: 2 PID: 9919 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3801 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3891 [inline] slab_alloc_node mm/slub.c:3981 [inline] kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020 btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411 alloc_inode+0x5d/0x230 fs/inode.c:261 iget5_locked fs/inode.c:1235 [inline] iget5_locked+0x1c9/0x2c0 fs/inode.c:1228 btrfs_iget_locked fs/btrfs/inode.c:5590 [inline] btrfs_iget_path fs/btrfs/inode.c:5607 [inline] btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636 add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline] copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928 btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592 log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline] btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718 btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline] btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141 btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180 btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959 vfs_fsync_range+0x141/0x230 fs/sync.c:188 generic_write_sync include/linux/fs.h:2794 [inline] btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705 do_iter_readv_writev+0x504/0x780 fs/read_write.c:741 vfs_writev+0x36f/0xde0 fs/read_write.c:971 do_pwritev+0x1b2/0x260 fs/read_write.c:1072 __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline] __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline] __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7334579 Code: b8 01 10 06 03 (...) RSP: 002b:00000000f5f265ac EFLAGS: 00000292 ORIG_RAX: 000000000000017b RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000200002c0 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Fix this by ensuring we are under a NOFS scope whenever we call btrfs_iget() during inode logging and log replay. Reported-by: syzbot+8576cfa84070dce4d59b@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/000000000000274a3a061abbd928@google.com/ Fixes: 712e36c ("btrfs: use GFP_KERNEL in btrfs_alloc_inode") Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
ptr1337
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Jul 11, 2024
commit be346c1 upstream. The code in ocfs2_dio_end_io_write() estimates number of necessary transaction credits using ocfs2_calc_extend_credits(). This however does not take into account that the IO could be arbitrarily large and can contain arbitrary number of extents. Extent tree manipulations do often extend the current transaction but not in all of the cases. For example if we have only single block extents in the tree, ocfs2_mark_extent_written() will end up calling ocfs2_replace_extent_rec() all the time and we will never extend the current transaction and eventually exhaust all the transaction credits if the IO contains many single block extents. Once that happens a WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to this error. This was actually triggered by one of our customers on a heavily fragmented OCFS2 filesystem. To fix the issue make sure the transaction always has enough credits for one extent insert before each call of ocfs2_mark_extent_written(). Heming Zhao said: ------ PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error" PID: xxx TASK: xxxx CPU: 5 COMMAND: "SubmitThread-CA" #0 machine_kexec at ffffffff8c069932 #1 __crash_kexec at ffffffff8c1338fa #2 panic at ffffffff8c1d69b9 #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2] #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2] #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2] torvalds#6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2] torvalds#7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2] torvalds#8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2] torvalds#9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2] torvalds#10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2] torvalds#11 dio_complete at ffffffff8c2b9fa7 torvalds#12 do_blockdev_direct_IO at ffffffff8c2bc09f torvalds#13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2] torvalds#14 generic_file_direct_write at ffffffff8c1dcf14 torvalds#15 __generic_file_write_iter at ffffffff8c1dd07b torvalds#16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2] torvalds#17 aio_write at ffffffff8c2cc72e torvalds#18 kmem_cache_alloc at ffffffff8c248dde torvalds#19 do_io_submit at ffffffff8c2ccada torvalds#20 do_syscall_64 at ffffffff8c004984 torvalds#21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io") Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by: Heming Zhao <heming.zhao@suse.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Jul 11, 2024
[ Upstream commit 3b3b84a ] As reported by Jose E. Marchesi in off-list discussion, GCC and LLVM generate slightly different code for dummy_st_ops_success/test_1(): SEC("struct_ops/test_1") int BPF_PROG(test_1, struct bpf_dummy_ops_state *state) { int ret; if (!state) return 0xf2f3f4f5; ret = state->val; state->val = 0x5a; return ret; } GCC-generated LLVM-generated ---------------------------- --------------------------- 0: r1 = *(u64 *)(r1 + 0x0) 0: w0 = -0xd0c0b0b 1: if r1 == 0x0 goto 5f 1: r1 = *(u64 *)(r1 + 0x0) 2: r0 = *(s32 *)(r1 + 0x0) 2: if r1 == 0x0 goto 6f 3: *(u32 *)(r1 + 0x0) = 0x5a 3: r0 = *(u32 *)(r1 + 0x0) 4: exit 4: w2 = 0x5a 5: r0 = -0xd0c0b0b 5: *(u32 *)(r1 + 0x0) = r2 6: exit 6: exit If the 'state' argument is not marked as nullable in net/bpf/bpf_dummy_struct_ops.c, the verifier would assume that 'r1 == 0x0' is never true: - for the GCC version, this means that instructions #5-6 would be marked as dead and removed; - for the LLVM version, all instructions would be marked as live. The test dummy_st_ops/dummy_init_ret_value actually sets the 'state' parameter to NULL. Therefore, when the 'state' argument is not marked as nullable, the GCC-generated version of the code would trigger a NULL pointer dereference at instruction #3. This patch updates the test_1() test case to always follow a shape similar to the GCC-generated version above, in order to verify whether the 'state' nullability is marked correctly. Reported-by: Jose E. Marchesi <jemarch@gnu.org> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240424012821.595216-3-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit d99fbd9 upstream. Bos can be put with multiple unrelated dma-resv locks held. But imported bos attempt to grab the bo dma-resv during dma-buf detach that typically happens during cleanup. That leads to lockde splats similar to the below and a potential ABBA deadlock. Fix this by always taking the delayed workqueue cleanup path for imported bos. Requesting stable fixes from when the Xe driver was introduced, since its usage of drm_exec and wide vm dma_resvs appear to be the first reliable trigger of this. [22982.116427] ============================================ [22982.116428] WARNING: possible recursive locking detected [22982.116429] 6.10.0-rc2+ torvalds#10 Tainted: G U W [22982.116430] -------------------------------------------- [22982.116430] glxgears:sh0/5785 is trying to acquire lock: [22982.116431] ffff8c2bafa539a8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_detach+0x3b/0xf0 [22982.116438] but task is already holding lock: [22982.116438] ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116442] other info that might help us debug this: [22982.116442] Possible unsafe locking scenario: [22982.116443] CPU0 [22982.116444] ---- [22982.116444] lock(reservation_ww_class_mutex); [22982.116445] lock(reservation_ww_class_mutex); [22982.116447] *** DEADLOCK *** [22982.116447] May be due to missing lock nesting notation [22982.116448] 5 locks held by glxgears:sh0/5785: [22982.116449] #0: ffff8c2d9aba58c8 (&xef->vm.lock){+.+.}-{3:3}, at: xe_file_close+0xde/0x1c0 [xe] [22982.116507] #1: ffff8c2e28cc8480 (&vm->lock){++++}-{3:3}, at: xe_vm_close_and_put+0x161/0x9b0 [xe] [22982.116578] #2: ffff8c2e31982970 (&val->lock){.+.+}-{3:3}, at: xe_validation_ctx_init+0x6d/0x70 [xe] [22982.116647] #3: ffffacdc469478a8 (reservation_ww_class_acquire){+.+.}-{0:0}, at: xe_vma_destroy_unlocked+0x7f/0xe0 [xe] [22982.116716] #4: ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116719] stack backtrace: [22982.116720] CPU: 8 PID: 5785 Comm: glxgears:sh0 Tainted: G U W 6.10.0-rc2+ torvalds#10 [22982.116721] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023 [22982.116723] Call Trace: [22982.116724] <TASK> [22982.116725] dump_stack_lvl+0x77/0xb0 [22982.116727] __lock_acquire+0x1232/0x2160 [22982.116730] lock_acquire+0xcb/0x2d0 [22982.116732] ? dma_buf_detach+0x3b/0xf0 [22982.116734] ? __lock_acquire+0x417/0x2160 [22982.116736] __ww_mutex_lock.constprop.0+0xd0/0x13b0 [22982.116738] ? dma_buf_detach+0x3b/0xf0 [22982.116741] ? dma_buf_detach+0x3b/0xf0 [22982.116743] ? ww_mutex_lock+0x2b/0x90 [22982.116745] ww_mutex_lock+0x2b/0x90 [22982.116747] dma_buf_detach+0x3b/0xf0 [22982.116749] drm_prime_gem_destroy+0x2f/0x40 [drm] [22982.116775] xe_ttm_bo_destroy+0x32/0x220 [xe] [22982.116818] ? __mutex_unlock_slowpath+0x3a/0x290 [22982.116821] drm_exec_unlock_all+0xa1/0xd0 [drm_exec] [22982.116823] drm_exec_fini+0x12/0xb0 [drm_exec] [22982.116824] xe_validation_ctx_fini+0x15/0x40 [xe] [22982.116892] xe_vma_destroy_unlocked+0xb1/0xe0 [xe] [22982.116959] xe_vm_close_and_put+0x41a/0x9b0 [xe] [22982.117025] ? xa_find+0xe3/0x1e0 [22982.117028] xe_file_close+0x10a/0x1c0 [xe] [22982.117074] drm_file_free+0x22a/0x280 [drm] [22982.117099] drm_release_noglobal+0x22/0x70 [drm] [22982.117119] __fput+0xf1/0x2d0 [22982.117122] task_work_run+0x59/0x90 [22982.117125] do_exit+0x330/0xb40 [22982.117127] do_group_exit+0x36/0xa0 [22982.117129] get_signal+0xbd2/0xbe0 [22982.117131] arch_do_signal_or_restart+0x3e/0x240 [22982.117134] syscall_exit_to_user_mode+0x1e7/0x290 [22982.117137] do_syscall_64+0xa1/0x180 [22982.117139] ? lock_acquire+0xcb/0x2d0 [22982.117140] ? __set_task_comm+0x28/0x1e0 [22982.117141] ? find_held_lock+0x2b/0x80 [22982.117144] ? __set_task_comm+0xe1/0x1e0 [22982.117145] ? lock_release+0xca/0x290 [22982.117147] ? __do_sys_prctl+0x245/0xab0 [22982.117149] ? lockdep_hardirqs_on_prepare+0xde/0x190 [22982.117150] ? syscall_exit_to_user_mode+0xb0/0x290 [22982.117152] ? do_syscall_64+0xa1/0x180 [22982.117154] ? __lock_acquire+0x417/0x2160 [22982.117155] ? reacquire_held_locks+0xd1/0x1f0 [22982.117156] ? do_user_addr_fault+0x30c/0x790 [22982.117158] ? lock_acquire+0xcb/0x2d0 [22982.117160] ? find_held_lock+0x2b/0x80 [22982.117162] ? do_user_addr_fault+0x357/0x790 [22982.117163] ? lock_release+0xca/0x290 [22982.117164] ? do_user_addr_fault+0x361/0x790 [22982.117166] ? trace_hardirqs_off+0x4b/0xc0 [22982.117168] ? clear_bhb_loop+0x45/0xa0 [22982.117170] ? clear_bhb_loop+0x45/0xa0 [22982.117172] ? clear_bhb_loop+0x45/0xa0 [22982.117174] entry_SYSCALL_64_after_hwframe+0x76/0x7e [22982.117176] RIP: 0033:0x7f943d267169 [22982.117192] Code: Unable to access opcode bytes at 0x7f943d26713f. [22982.117193] RSP: 002b:00007f9430bffc80 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [22982.117195] RAX: fffffffffffffe00 RBX: 0000000000000000 RCX: 00007f943d267169 [22982.117196] RDX: 0000000000000000 RSI: 0000000000000189 RDI: 00005622f89579d0 [22982.117197] RBP: 00007f9430bffcb0 R08: 0000000000000000 R09: 00000000ffffffff [22982.117198] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [22982.117199] R13: 0000000000000000 R14: 0000000000000000 R15: 00005622f89579d0 [22982.117202] </TASK> Fixes: dd08ebf ("drm/xe: Introduce a new DRM driver for Intel GPUs") Cc: Christian König <christian.koenig@amd.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: dri-devel@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Cc: <stable@vger.kernel.org> # v6.8+ Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240628153848.4989-1-thomas.hellstrom@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ptr1337
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Jul 12, 2024
Bos can be put with multiple unrelated dma-resv locks held. But imported bos attempt to grab the bo dma-resv during dma-buf detach that typically happens during cleanup. That leads to lockde splats similar to the below and a potential ABBA deadlock. Fix this by always taking the delayed workqueue cleanup path for imported bos. Requesting stable fixes from when the Xe driver was introduced, since its usage of drm_exec and wide vm dma_resvs appear to be the first reliable trigger of this. [22982.116427] ============================================ [22982.116428] WARNING: possible recursive locking detected [22982.116429] 6.10.0-rc2+ torvalds#10 Tainted: G U W [22982.116430] -------------------------------------------- [22982.116430] glxgears:sh0/5785 is trying to acquire lock: [22982.116431] ffff8c2bafa539a8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_detach+0x3b/0xf0 [22982.116438] but task is already holding lock: [22982.116438] ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116442] other info that might help us debug this: [22982.116442] Possible unsafe locking scenario: [22982.116443] CPU0 [22982.116444] ---- [22982.116444] lock(reservation_ww_class_mutex); [22982.116445] lock(reservation_ww_class_mutex); [22982.116447] *** DEADLOCK *** [22982.116447] May be due to missing lock nesting notation [22982.116448] 5 locks held by glxgears:sh0/5785: [22982.116449] #0: ffff8c2d9aba58c8 (&xef->vm.lock){+.+.}-{3:3}, at: xe_file_close+0xde/0x1c0 [xe] [22982.116507] #1: ffff8c2e28cc8480 (&vm->lock){++++}-{3:3}, at: xe_vm_close_and_put+0x161/0x9b0 [xe] [22982.116578] #2: ffff8c2e31982970 (&val->lock){.+.+}-{3:3}, at: xe_validation_ctx_init+0x6d/0x70 [xe] [22982.116647] #3: ffffacdc469478a8 (reservation_ww_class_acquire){+.+.}-{0:0}, at: xe_vma_destroy_unlocked+0x7f/0xe0 [xe] [22982.116716] #4: ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116719] stack backtrace: [22982.116720] CPU: 8 PID: 5785 Comm: glxgears:sh0 Tainted: G U W 6.10.0-rc2+ torvalds#10 [22982.116721] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023 [22982.116723] Call Trace: [22982.116724] <TASK> [22982.116725] dump_stack_lvl+0x77/0xb0 [22982.116727] __lock_acquire+0x1232/0x2160 [22982.116730] lock_acquire+0xcb/0x2d0 [22982.116732] ? dma_buf_detach+0x3b/0xf0 [22982.116734] ? __lock_acquire+0x417/0x2160 [22982.116736] __ww_mutex_lock.constprop.0+0xd0/0x13b0 [22982.116738] ? dma_buf_detach+0x3b/0xf0 [22982.116741] ? dma_buf_detach+0x3b/0xf0 [22982.116743] ? ww_mutex_lock+0x2b/0x90 [22982.116745] ww_mutex_lock+0x2b/0x90 [22982.116747] dma_buf_detach+0x3b/0xf0 [22982.116749] drm_prime_gem_destroy+0x2f/0x40 [drm] [22982.116775] xe_ttm_bo_destroy+0x32/0x220 [xe] [22982.116818] ? __mutex_unlock_slowpath+0x3a/0x290 [22982.116821] drm_exec_unlock_all+0xa1/0xd0 [drm_exec] [22982.116823] drm_exec_fini+0x12/0xb0 [drm_exec] [22982.116824] xe_validation_ctx_fini+0x15/0x40 [xe] [22982.116892] xe_vma_destroy_unlocked+0xb1/0xe0 [xe] [22982.116959] xe_vm_close_and_put+0x41a/0x9b0 [xe] [22982.117025] ? xa_find+0xe3/0x1e0 [22982.117028] xe_file_close+0x10a/0x1c0 [xe] [22982.117074] drm_file_free+0x22a/0x280 [drm] [22982.117099] drm_release_noglobal+0x22/0x70 [drm] [22982.117119] __fput+0xf1/0x2d0 [22982.117122] task_work_run+0x59/0x90 [22982.117125] do_exit+0x330/0xb40 [22982.117127] do_group_exit+0x36/0xa0 [22982.117129] get_signal+0xbd2/0xbe0 [22982.117131] arch_do_signal_or_restart+0x3e/0x240 [22982.117134] syscall_exit_to_user_mode+0x1e7/0x290 [22982.117137] do_syscall_64+0xa1/0x180 [22982.117139] ? lock_acquire+0xcb/0x2d0 [22982.117140] ? __set_task_comm+0x28/0x1e0 [22982.117141] ? find_held_lock+0x2b/0x80 [22982.117144] ? __set_task_comm+0xe1/0x1e0 [22982.117145] ? lock_release+0xca/0x290 [22982.117147] ? __do_sys_prctl+0x245/0xab0 [22982.117149] ? lockdep_hardirqs_on_prepare+0xde/0x190 [22982.117150] ? syscall_exit_to_user_mode+0xb0/0x290 [22982.117152] ? do_syscall_64+0xa1/0x180 [22982.117154] ? __lock_acquire+0x417/0x2160 [22982.117155] ? reacquire_held_locks+0xd1/0x1f0 [22982.117156] ? do_user_addr_fault+0x30c/0x790 [22982.117158] ? lock_acquire+0xcb/0x2d0 [22982.117160] ? find_held_lock+0x2b/0x80 [22982.117162] ? do_user_addr_fault+0x357/0x790 [22982.117163] ? lock_release+0xca/0x290 [22982.117164] ? do_user_addr_fault+0x361/0x790 [22982.117166] ? trace_hardirqs_off+0x4b/0xc0 [22982.117168] ? clear_bhb_loop+0x45/0xa0 [22982.117170] ? clear_bhb_loop+0x45/0xa0 [22982.117172] ? clear_bhb_loop+0x45/0xa0 [22982.117174] entry_SYSCALL_64_after_hwframe+0x76/0x7e [22982.117176] RIP: 0033:0x7f943d267169 [22982.117192] Code: Unable to access opcode bytes at 0x7f943d26713f. [22982.117193] RSP: 002b:00007f9430bffc80 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [22982.117195] RAX: fffffffffffffe00 RBX: 0000000000000000 RCX: 00007f943d267169 [22982.117196] RDX: 0000000000000000 RSI: 0000000000000189 RDI: 00005622f89579d0 [22982.117197] RBP: 00007f9430bffcb0 R08: 0000000000000000 R09: 00000000ffffffff [22982.117198] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [22982.117199] R13: 0000000000000000 R14: 0000000000000000 R15: 00005622f89579d0 [22982.117202] </TASK> Fixes: dd08ebf ("drm/xe: Introduce a new DRM driver for Intel GPUs") Cc: Christian König <christian.koenig@amd.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: dri-devel@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Cc: <stable@vger.kernel.org> # v6.8+ Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240628153848.4989-1-thomas.hellstrom@linux.intel.com
ptr1337
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Jul 15, 2024
When putting an inode during extent map shrinking we're doing a standard
iput() but that may take a long time in case the inode is dirty and we are
doing the final iput that triggers eviction - the VFS will have to wait
for writeback before calling the btrfs evict callback (see
fs/inode.c:evict()).
This slows down the task running the shrinker which may have been
triggered while updating some tree for example, meaning locks are held
as well as an open transaction handle.
Also if the iput() ends up triggering eviction and the inode has no links
anymore, then we trigger item truncation which requires flushing delayed
items, space reservation to start a transaction and that may trigger the
space reclaim task and wait for it, resulting in deadlocks in case the
reclaim task needs for example to commit a transaction and the shrinker
is being triggered from a path holding a transaction handle.
Syzbot reported such a case with the following stack traces:
======================================================
WARNING: possible circular locking dependency detected
6.10.0-rc2-syzkaller-00010-g2ab795141095 #0 Not tainted
------------------------------------------------------
kswapd0/111 is trying to acquire lock:
ffff88801eae4610 (sb_internal#3){.+.+}-{0:0}, at: btrfs_commit_inode_delayed_inode+0x110/0x330 fs/btrfs/delayed-inode.c:1275
but task is already holding lock:
ffffffff8dd3a9a0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xa88/0x1970 mm/vmscan.c:6924
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (fs_reclaim){+.+.}-{0:0}:
__fs_reclaim_acquire mm/page_alloc.c:3783 [inline]
fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3797
might_alloc include/linux/sched/mm.h:334 [inline]
slab_pre_alloc_hook mm/slub.c:3890 [inline]
slab_alloc_node mm/slub.c:3980 [inline]
kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4019
btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411
alloc_inode+0x5d/0x230 fs/inode.c:261
iget5_locked fs/inode.c:1235 [inline]
iget5_locked+0x1c9/0x2c0 fs/inode.c:1228
btrfs_iget_locked fs/btrfs/inode.c:5590 [inline]
btrfs_iget_path fs/btrfs/inode.c:5607 [inline]
btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636
create_reloc_inode+0x403/0x820 fs/btrfs/relocation.c:3911
btrfs_relocate_block_group+0x471/0xe60 fs/btrfs/relocation.c:4114
btrfs_relocate_chunk+0x143/0x450 fs/btrfs/volumes.c:3373
__btrfs_balance fs/btrfs/volumes.c:4157 [inline]
btrfs_balance+0x211a/0x3f00 fs/btrfs/volumes.c:4534
btrfs_ioctl_balance fs/btrfs/ioctl.c:3675 [inline]
btrfs_ioctl+0x12ed/0x8290 fs/btrfs/ioctl.c:4742
__do_compat_sys_ioctl+0x2c3/0x330 fs/ioctl.c:1007
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
-> #2 (btrfs_trans_num_extwriters){++++}-{0:0}:
join_transaction+0x164/0xf40 fs/btrfs/transaction.c:315
start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700
btrfs_rebuild_free_space_tree+0xaa/0x480 fs/btrfs/free-space-tree.c:1323
btrfs_start_pre_rw_mount+0x218/0xf60 fs/btrfs/disk-io.c:2999
open_ctree+0x41ab/0x52e0 fs/btrfs/disk-io.c:3554
btrfs_fill_super fs/btrfs/super.c:946 [inline]
btrfs_get_tree_super fs/btrfs/super.c:1863 [inline]
btrfs_get_tree+0x11e9/0x1b90 fs/btrfs/super.c:2089
vfs_get_tree+0x8f/0x380 fs/super.c:1780
fc_mount+0x16/0xc0 fs/namespace.c:1125
btrfs_get_tree_subvol fs/btrfs/super.c:2052 [inline]
btrfs_get_tree+0xa53/0x1b90 fs/btrfs/super.c:2090
vfs_get_tree+0x8f/0x380 fs/super.c:1780
do_new_mount fs/namespace.c:3352 [inline]
path_mount+0x6e1/0x1f10 fs/namespace.c:3679
do_mount fs/namespace.c:3692 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount fs/namespace.c:3875 [inline]
__ia32_sys_mount+0x295/0x320 fs/namespace.c:3875
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
-> #1 (btrfs_trans_num_writers){++++}-{0:0}:
join_transaction+0x148/0xf40 fs/btrfs/transaction.c:314
start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700
btrfs_rebuild_free_space_tree+0xaa/0x480 fs/btrfs/free-space-tree.c:1323
btrfs_start_pre_rw_mount+0x218/0xf60 fs/btrfs/disk-io.c:2999
open_ctree+0x41ab/0x52e0 fs/btrfs/disk-io.c:3554
btrfs_fill_super fs/btrfs/super.c:946 [inline]
btrfs_get_tree_super fs/btrfs/super.c:1863 [inline]
btrfs_get_tree+0x11e9/0x1b90 fs/btrfs/super.c:2089
vfs_get_tree+0x8f/0x380 fs/super.c:1780
fc_mount+0x16/0xc0 fs/namespace.c:1125
btrfs_get_tree_subvol fs/btrfs/super.c:2052 [inline]
btrfs_get_tree+0xa53/0x1b90 fs/btrfs/super.c:2090
vfs_get_tree+0x8f/0x380 fs/super.c:1780
do_new_mount fs/namespace.c:3352 [inline]
path_mount+0x6e1/0x1f10 fs/namespace.c:3679
do_mount fs/namespace.c:3692 [inline]
__do_sys_mount fs/namespace.c:3898 [inline]
__se_sys_mount fs/namespace.c:3875 [inline]
__ia32_sys_mount+0x295/0x320 fs/namespace.c:3875
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
-> #0 (sb_internal#3){.+.+}-{0:0}:
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1655 [inline]
sb_start_intwrite include/linux/fs.h:1838 [inline]
start_transaction+0xbc1/0x1a70 fs/btrfs/transaction.c:694
btrfs_commit_inode_delayed_inode+0x110/0x330 fs/btrfs/delayed-inode.c:1275
btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291
evict+0x2ed/0x6c0 fs/inode.c:667
iput_final fs/inode.c:1741 [inline]
iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
iput+0x5c/0x80 fs/inode.c:1757
btrfs_scan_root fs/btrfs/extent_map.c:1118 [inline]
btrfs_free_extent_maps+0xbd3/0x1320 fs/btrfs/extent_map.c:1189
super_cache_scan+0x409/0x550 fs/super.c:227
do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
shrink_slab+0x18a/0x1310 mm/shrinker.c:662
shrink_one+0x493/0x7c0 mm/vmscan.c:4790
shrink_many mm/vmscan.c:4851 [inline]
lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
shrink_node mm/vmscan.c:5910 [inline]
kswapd_shrink_node mm/vmscan.c:6720 [inline]
balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
other info that might help us debug this:
Chain exists of:
sb_internal#3 --> btrfs_trans_num_extwriters --> fs_reclaim
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(btrfs_trans_num_extwriters);
lock(fs_reclaim);
rlock(sb_internal#3);
*** DEADLOCK ***
2 locks held by kswapd0/111:
#0: ffffffff8dd3a9a0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xa88/0x1970 mm/vmscan.c:6924
#1: ffff88801eae40e0 (&type->s_umount_key#62){++++}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline]
#1: ffff88801eae40e0 (&type->s_umount_key#62){++++}-{3:3}, at: super_cache_scan+0x96/0x550 fs/super.c:196
stack backtrace:
CPU: 0 PID: 111 Comm: kswapd0 Not tainted 6.10.0-rc2-syzkaller-00010-g2ab795141095 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187
check_prev_add kernel/locking/lockdep.c:3134 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain kernel/locking/lockdep.c:3869 [inline]
__lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
lock_acquire kernel/locking/lockdep.c:5754 [inline]
lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1655 [inline]
sb_start_intwrite include/linux/fs.h:1838 [inline]
start_transaction+0xbc1/0x1a70 fs/btrfs/transaction.c:694
btrfs_commit_inode_delayed_inode+0x110/0x330 fs/btrfs/delayed-inode.c:1275
btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291
evict+0x2ed/0x6c0 fs/inode.c:667
iput_final fs/inode.c:1741 [inline]
iput.part.0+0x5a8/0x7f0 fs/inode.c:1767
iput+0x5c/0x80 fs/inode.c:1757
btrfs_scan_root fs/btrfs/extent_map.c:1118 [inline]
btrfs_free_extent_maps+0xbd3/0x1320 fs/btrfs/extent_map.c:1189
super_cache_scan+0x409/0x550 fs/super.c:227
do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435
shrink_slab+0x18a/0x1310 mm/shrinker.c:662
shrink_one+0x493/0x7c0 mm/vmscan.c:4790
shrink_many mm/vmscan.c:4851 [inline]
lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951
shrink_node mm/vmscan.c:5910 [inline]
kswapd_shrink_node mm/vmscan.c:6720 [inline]
balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911
kswapd+0x5ea/0xbf0 mm/vmscan.c:7180
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
So fix this by using btrfs_add_delayed_iput() so that the final iput is
delegated to the cleaner kthread.
Link: https://lore.kernel.org/linux-btrfs/000000000000892280061a344581@google.com/
Reported-by: syzbot+3dad89b3993a4b275e72@syzkaller.appspotmail.com
Fixes: 956a17d ("btrfs: add a shrinker for extent maps")
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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…_child(). [ Upstream commit 3f45181 ] syzkaller reported KMSAN splat in tcp_create_openreq_child(). [0] The uninit variable is tcp_rsk(req)->ao_keyid. tcp_rsk(req)->ao_keyid is initialised only when tcp_conn_request() finds a valid TCP AO option in SYN. Then, tcp_rsk(req)->used_tcp_ao is set accordingly. Let's not read tcp_rsk(req)->ao_keyid when tcp_rsk(req)->used_tcp_ao is false. [0]: BUG: KMSAN: uninit-value in tcp_create_openreq_child+0x198b/0x1ff0 net/ipv4/tcp_minisocks.c:610 tcp_create_openreq_child+0x198b/0x1ff0 net/ipv4/tcp_minisocks.c:610 tcp_v4_syn_recv_sock+0x18e/0x2170 net/ipv4/tcp_ipv4.c:1754 tcp_check_req+0x1a3e/0x20c0 net/ipv4/tcp_minisocks.c:852 tcp_v4_rcv+0x26a4/0x53a0 net/ipv4/tcp_ipv4.c:2265 ip_protocol_deliver_rcu+0x884/0x1270 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x30f/0x530 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] ip_local_deliver+0x230/0x4c0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline] ip_sublist_rcv+0x10f7/0x13e0 net/ipv4/ip_input.c:639 ip_list_rcv+0x952/0x9c0 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5703 [inline] __netif_receive_skb_list_core+0xd92/0x11d0 net/core/dev.c:5751 __netif_receive_skb_list net/core/dev.c:5803 [inline] netif_receive_skb_list_internal+0xd8f/0x1350 net/core/dev.c:5895 gro_normal_list include/net/gro.h:515 [inline] napi_complete_done+0x3f2/0x990 net/core/dev.c:6246 e1000_clean+0x1fa4/0x5e50 drivers/net/ethernet/intel/e1000/e1000_main.c:3808 __napi_poll+0xd9/0x990 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x90f/0x17e0 net/core/dev.c:6962 handle_softirqs+0x152/0x6b0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0x5d/0x120 kernel/softirq.c:649 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 __msan_instrument_asm_store+0xd6/0xe0 arch_atomic_inc arch/x86/include/asm/atomic.h:53 [inline] raw_atomic_inc include/linux/atomic/atomic-arch-fallback.h:992 [inline] atomic_inc include/linux/atomic/atomic-instrumented.h:436 [inline] page_ref_inc include/linux/page_ref.h:153 [inline] folio_ref_inc include/linux/page_ref.h:160 [inline] filemap_map_order0_folio mm/filemap.c:3596 [inline] filemap_map_pages+0x11c7/0x2270 mm/filemap.c:3644 do_fault_around mm/memory.c:4879 [inline] do_read_fault mm/memory.c:4912 [inline] do_fault mm/memory.c:5051 [inline] do_pte_missing mm/memory.c:3897 [inline] handle_pte_fault mm/memory.c:5381 [inline] __handle_mm_fault mm/memory.c:5524 [inline] handle_mm_fault+0x3677/0x6f00 mm/memory.c:5689 do_user_addr_fault+0x1373/0x2b20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x54/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 Uninit was stored to memory at: tcp_create_openreq_child+0x1984/0x1ff0 net/ipv4/tcp_minisocks.c:611 tcp_v4_syn_recv_sock+0x18e/0x2170 net/ipv4/tcp_ipv4.c:1754 tcp_check_req+0x1a3e/0x20c0 net/ipv4/tcp_minisocks.c:852 tcp_v4_rcv+0x26a4/0x53a0 net/ipv4/tcp_ipv4.c:2265 ip_protocol_deliver_rcu+0x884/0x1270 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x30f/0x530 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] ip_local_deliver+0x230/0x4c0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline] ip_sublist_rcv+0x10f7/0x13e0 net/ipv4/ip_input.c:639 ip_list_rcv+0x952/0x9c0 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5703 [inline] __netif_receive_skb_list_core+0xd92/0x11d0 net/core/dev.c:5751 __netif_receive_skb_list net/core/dev.c:5803 [inline] netif_receive_skb_list_internal+0xd8f/0x1350 net/core/dev.c:5895 gro_normal_list include/net/gro.h:515 [inline] napi_complete_done+0x3f2/0x990 net/core/dev.c:6246 e1000_clean+0x1fa4/0x5e50 drivers/net/ethernet/intel/e1000/e1000_main.c:3808 __napi_poll+0xd9/0x990 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x90f/0x17e0 net/core/dev.c:6962 handle_softirqs+0x152/0x6b0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0x5d/0x120 kernel/softirq.c:649 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 Uninit was created at: __alloc_pages_noprof+0x82d/0xcb0 mm/page_alloc.c:4706 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page mm/slub.c:2265 [inline] allocate_slab mm/slub.c:2428 [inline] new_slab+0x2af/0x14e0 mm/slub.c:2481 ___slab_alloc+0xf73/0x3150 mm/slub.c:3667 __slab_alloc mm/slub.c:3757 [inline] __slab_alloc_node mm/slub.c:3810 [inline] slab_alloc_node mm/slub.c:3990 [inline] kmem_cache_alloc_noprof+0x53a/0x9f0 mm/slub.c:4009 reqsk_alloc_noprof net/ipv4/inet_connection_sock.c:920 [inline] inet_reqsk_alloc+0x63/0x700 net/ipv4/inet_connection_sock.c:951 tcp_conn_request+0x339/0x4860 net/ipv4/tcp_input.c:7177 tcp_v4_conn_request+0x13b/0x190 net/ipv4/tcp_ipv4.c:1719 tcp_rcv_state_process+0x2dd/0x4a10 net/ipv4/tcp_input.c:6711 tcp_v4_do_rcv+0xbee/0x10d0 net/ipv4/tcp_ipv4.c:1932 tcp_v4_rcv+0x3fad/0x53a0 net/ipv4/tcp_ipv4.c:2334 ip_protocol_deliver_rcu+0x884/0x1270 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x30f/0x530 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] ip_local_deliver+0x230/0x4c0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline] ip_sublist_rcv+0x10f7/0x13e0 net/ipv4/ip_input.c:639 ip_list_rcv+0x952/0x9c0 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5703 [inline] __netif_receive_skb_list_core+0xd92/0x11d0 net/core/dev.c:5751 __netif_receive_skb_list net/core/dev.c:5803 [inline] netif_receive_skb_list_internal+0xd8f/0x1350 net/core/dev.c:5895 gro_normal_list include/net/gro.h:515 [inline] napi_complete_done+0x3f2/0x990 net/core/dev.c:6246 e1000_clean+0x1fa4/0x5e50 drivers/net/ethernet/intel/e1000/e1000_main.c:3808 __napi_poll+0xd9/0x990 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x90f/0x17e0 net/core/dev.c:6962 handle_softirqs+0x152/0x6b0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0x5d/0x120 kernel/softirq.c:649 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 CPU: 0 PID: 239 Comm: modprobe Tainted: G B 6.10.0-rc7-01816-g852e42cc2dd4 #3 1107521f0c7b55c9309062382d0bda9f604dbb6d Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Fixes: 06b22ef ("net/tcp: Wire TCP-AO to request sockets") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Dmitry Safonov <0x7f454c46@gmail.com> Link: https://patch.msgid.link/20240714161719.6528-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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Aug 3, 2024
commit 667574e upstream. When tries to demote 1G hugetlb folios, a lockdep warning is observed: ============================================ WARNING: possible recursive locking detected 6.10.0-rc6-00452-ga4d0275fa660-dirty torvalds#79 Not tainted -------------------------------------------- bash/710 is trying to acquire lock: ffffffff8f0a7850 (&h->resize_lock){+.+.}-{3:3}, at: demote_store+0x244/0x460 but task is already holding lock: ffffffff8f0a6f48 (&h->resize_lock){+.+.}-{3:3}, at: demote_store+0xae/0x460 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&h->resize_lock); lock(&h->resize_lock); *** DEADLOCK *** May be due to missing lock nesting notation 4 locks held by bash/710: #0: ffff8f118439c3f0 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x64/0xe0 #1: ffff8f11893b9e88 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xf8/0x1d0 #2: ffff8f1183dc4428 (kn->active#98){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x100/0x1d0 #3: ffffffff8f0a6f48 (&h->resize_lock){+.+.}-{3:3}, at: demote_store+0xae/0x460 stack backtrace: CPU: 3 PID: 710 Comm: bash Not tainted 6.10.0-rc6-00452-ga4d0275fa660-dirty torvalds#79 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x68/0xa0 __lock_acquire+0x10f2/0x1ca0 lock_acquire+0xbe/0x2d0 __mutex_lock+0x6d/0x400 demote_store+0x244/0x460 kernfs_fop_write_iter+0x12c/0x1d0 vfs_write+0x380/0x540 ksys_write+0x64/0xe0 do_syscall_64+0xb9/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa61db14887 RSP: 002b:00007ffc56c48358 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fa61db14887 RDX: 0000000000000002 RSI: 000055a030050220 RDI: 0000000000000001 RBP: 000055a030050220 R08: 00007fa61dbd1460 R09: 000000007fffffff R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007fa61dc1b780 R14: 00007fa61dc17600 R15: 00007fa61dc16a00 </TASK> Lockdep considers this an AA deadlock because the different resize_lock mutexes reside in the same lockdep class, but this is a false positive. Place them in distinct classes to avoid these warnings. Link: https://lkml.kernel.org/r/20240712031314.2570452-1-linmiaohe@huawei.com Fixes: 8531fc6 ("hugetlb: add hugetlb demote page support") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Muchun Song <muchun.song@linux.dev> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When l2tp tunnels use a socket provided by userspace, we can hit lockdep splats like the below when data is transmitted through another (unrelated) userspace socket which then gets routed over l2tp. This issue was previously discussed here: https://lore.kernel.org/netdev/87sfialu2n.fsf@cloudflare.com/ The solution is to have lockdep treat socket locks of l2tp tunnel sockets separately than those of standard INET sockets. To do so, use a different lockdep subclass where lock nesting is possible. ============================================ WARNING: possible recursive locking detected 6.10.0+ torvalds#34 Not tainted -------------------------------------------- iperf3/771 is trying to acquire lock: ffff8881027601d8 (slock-AF_INET/1){+.-.}-{2:2}, at: l2tp_xmit_skb+0x243/0x9d0 but task is already holding lock: ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(slock-AF_INET/1); lock(slock-AF_INET/1); *** DEADLOCK *** May be due to missing lock nesting notation 10 locks held by iperf3/771: #0: ffff888102650258 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sendmsg+0x1a/0x40 #1: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0 #2: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130 #3: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x28b/0x9f0 #4: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0xf9/0x260 #5: ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10 torvalds#6: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0 torvalds#7: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130 torvalds#8: ffffffff822ac1e0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0xcc/0x1450 torvalds#9: ffff888101f33258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}, at: __dev_queue_xmit+0x513/0x1450 stack backtrace: CPU: 2 UID: 0 PID: 771 Comm: iperf3 Not tainted 6.10.0+ torvalds#34 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <IRQ> dump_stack_lvl+0x69/0xa0 dump_stack+0xc/0x20 __lock_acquire+0x135d/0x2600 ? srso_alias_return_thunk+0x5/0xfbef5 lock_acquire+0xc4/0x2a0 ? l2tp_xmit_skb+0x243/0x9d0 ? __skb_checksum+0xa3/0x540 _raw_spin_lock_nested+0x35/0x50 ? l2tp_xmit_skb+0x243/0x9d0 l2tp_xmit_skb+0x243/0x9d0 l2tp_eth_dev_xmit+0x3c/0xc0 dev_hard_start_xmit+0x11e/0x420 sch_direct_xmit+0xc3/0x640 __dev_queue_xmit+0x61c/0x1450 ? ip_finish_output2+0xf4c/0x1130 ip_finish_output2+0x6b6/0x1130 ? srso_alias_return_thunk+0x5/0xfbef5 ? __ip_finish_output+0x217/0x380 ? srso_alias_return_thunk+0x5/0xfbef5 __ip_finish_output+0x217/0x380 ip_output+0x99/0x120 __ip_queue_xmit+0xae4/0xbc0 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? tcp_options_write.constprop.0+0xcb/0x3e0 ip_queue_xmit+0x34/0x40 __tcp_transmit_skb+0x1625/0x1890 __tcp_send_ack+0x1b8/0x340 tcp_send_ack+0x23/0x30 __tcp_ack_snd_check+0xa8/0x530 ? srso_alias_return_thunk+0x5/0xfbef5 tcp_rcv_established+0x412/0xd70 tcp_v4_do_rcv+0x299/0x420 tcp_v4_rcv+0x1991/0x1e10 ip_protocol_deliver_rcu+0x50/0x220 ip_local_deliver_finish+0x158/0x260 ip_local_deliver+0xc8/0xe0 ip_rcv+0xe5/0x1d0 ? __pfx_ip_rcv+0x10/0x10 __netif_receive_skb_one_core+0xce/0xe0 ? process_backlog+0x28b/0x9f0 __netif_receive_skb+0x34/0xd0 ? process_backlog+0x28b/0x9f0 process_backlog+0x2cb/0x9f0 __napi_poll.constprop.0+0x61/0x280 net_rx_action+0x332/0x670 ? srso_alias_return_thunk+0x5/0xfbef5 ? find_held_lock+0x2b/0x80 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 handle_softirqs+0xda/0x480 ? __dev_queue_xmit+0xa2c/0x1450 do_softirq+0xa1/0xd0 </IRQ> <TASK> __local_bh_enable_ip+0xc8/0xe0 ? __dev_queue_xmit+0xa2c/0x1450 __dev_queue_xmit+0xa48/0x1450 ? ip_finish_output2+0xf4c/0x1130 ip_finish_output2+0x6b6/0x1130 ? srso_alias_return_thunk+0x5/0xfbef5 ? __ip_finish_output+0x217/0x380 ? srso_alias_return_thunk+0x5/0xfbef5 __ip_finish_output+0x217/0x380 ip_output+0x99/0x120 __ip_queue_xmit+0xae4/0xbc0 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? tcp_options_write.constprop.0+0xcb/0x3e0 ip_queue_xmit+0x34/0x40 __tcp_transmit_skb+0x1625/0x1890 tcp_write_xmit+0x766/0x2fb0 ? __entry_text_end+0x102ba9/0x102bad ? srso_alias_return_thunk+0x5/0xfbef5 ? __might_fault+0x74/0xc0 ? srso_alias_return_thunk+0x5/0xfbef5 __tcp_push_pending_frames+0x56/0x190 tcp_push+0x117/0x310 tcp_sendmsg_locked+0x14c1/0x1740 tcp_sendmsg+0x28/0x40 inet_sendmsg+0x5d/0x90 sock_write_iter+0x242/0x2b0 vfs_write+0x68d/0x800 ? __pfx_sock_write_iter+0x10/0x10 ksys_write+0xc8/0xf0 __x64_sys_write+0x3d/0x50 x64_sys_call+0xfaf/0x1f50 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f4d143af992 Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> e9 01 cc ff ff 41 54 b8 02 00 00 0 RSP: 002b:00007ffd65032058 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f4d143af992 RDX: 0000000000000025 RSI: 00007f4d143f3bcc RDI: 0000000000000005 RBP: 00007f4d143f2b28 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4d143f3bcc R13: 0000000000000005 R14: 0000000000000000 R15: 00007ffd650323f0 </TASK> Fixes: 0b2c597 ("l2tp: close all race conditions in l2tp_tunnel_register()") Suggested-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot+6acef9e0a4d1f46c83d4@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=6acef9e0a4d1f46c83d4 CC: gnault@redhat.com CC: cong.wang@bytedance.com Signed-off-by: James Chapman <jchapman@katalix.com> Signed-off-by: Tom Parkin <tparkin@katalix.com> Link: https://patch.msgid.link/20240806160626.1248317-1-jchapman@katalix.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ptr1337
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Aug 14, 2024
[ Upstream commit 86a41ea ] When l2tp tunnels use a socket provided by userspace, we can hit lockdep splats like the below when data is transmitted through another (unrelated) userspace socket which then gets routed over l2tp. This issue was previously discussed here: https://lore.kernel.org/netdev/87sfialu2n.fsf@cloudflare.com/ The solution is to have lockdep treat socket locks of l2tp tunnel sockets separately than those of standard INET sockets. To do so, use a different lockdep subclass where lock nesting is possible. ============================================ WARNING: possible recursive locking detected 6.10.0+ torvalds#34 Not tainted -------------------------------------------- iperf3/771 is trying to acquire lock: ffff8881027601d8 (slock-AF_INET/1){+.-.}-{2:2}, at: l2tp_xmit_skb+0x243/0x9d0 but task is already holding lock: ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(slock-AF_INET/1); lock(slock-AF_INET/1); *** DEADLOCK *** May be due to missing lock nesting notation 10 locks held by iperf3/771: #0: ffff888102650258 (sk_lock-AF_INET){+.+.}-{0:0}, at: tcp_sendmsg+0x1a/0x40 #1: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0 #2: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130 #3: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x28b/0x9f0 #4: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0xf9/0x260 #5: ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10 torvalds#6: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0 torvalds#7: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130 torvalds#8: ffffffff822ac1e0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0xcc/0x1450 torvalds#9: ffff888101f33258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock#2){+...}-{2:2}, at: __dev_queue_xmit+0x513/0x1450 stack backtrace: CPU: 2 UID: 0 PID: 771 Comm: iperf3 Not tainted 6.10.0+ torvalds#34 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <IRQ> dump_stack_lvl+0x69/0xa0 dump_stack+0xc/0x20 __lock_acquire+0x135d/0x2600 ? srso_alias_return_thunk+0x5/0xfbef5 lock_acquire+0xc4/0x2a0 ? l2tp_xmit_skb+0x243/0x9d0 ? __skb_checksum+0xa3/0x540 _raw_spin_lock_nested+0x35/0x50 ? l2tp_xmit_skb+0x243/0x9d0 l2tp_xmit_skb+0x243/0x9d0 l2tp_eth_dev_xmit+0x3c/0xc0 dev_hard_start_xmit+0x11e/0x420 sch_direct_xmit+0xc3/0x640 __dev_queue_xmit+0x61c/0x1450 ? ip_finish_output2+0xf4c/0x1130 ip_finish_output2+0x6b6/0x1130 ? srso_alias_return_thunk+0x5/0xfbef5 ? __ip_finish_output+0x217/0x380 ? srso_alias_return_thunk+0x5/0xfbef5 __ip_finish_output+0x217/0x380 ip_output+0x99/0x120 __ip_queue_xmit+0xae4/0xbc0 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? tcp_options_write.constprop.0+0xcb/0x3e0 ip_queue_xmit+0x34/0x40 __tcp_transmit_skb+0x1625/0x1890 __tcp_send_ack+0x1b8/0x340 tcp_send_ack+0x23/0x30 __tcp_ack_snd_check+0xa8/0x530 ? srso_alias_return_thunk+0x5/0xfbef5 tcp_rcv_established+0x412/0xd70 tcp_v4_do_rcv+0x299/0x420 tcp_v4_rcv+0x1991/0x1e10 ip_protocol_deliver_rcu+0x50/0x220 ip_local_deliver_finish+0x158/0x260 ip_local_deliver+0xc8/0xe0 ip_rcv+0xe5/0x1d0 ? __pfx_ip_rcv+0x10/0x10 __netif_receive_skb_one_core+0xce/0xe0 ? process_backlog+0x28b/0x9f0 __netif_receive_skb+0x34/0xd0 ? process_backlog+0x28b/0x9f0 process_backlog+0x2cb/0x9f0 __napi_poll.constprop.0+0x61/0x280 net_rx_action+0x332/0x670 ? srso_alias_return_thunk+0x5/0xfbef5 ? find_held_lock+0x2b/0x80 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 handle_softirqs+0xda/0x480 ? __dev_queue_xmit+0xa2c/0x1450 do_softirq+0xa1/0xd0 </IRQ> <TASK> __local_bh_enable_ip+0xc8/0xe0 ? __dev_queue_xmit+0xa2c/0x1450 __dev_queue_xmit+0xa48/0x1450 ? ip_finish_output2+0xf4c/0x1130 ip_finish_output2+0x6b6/0x1130 ? srso_alias_return_thunk+0x5/0xfbef5 ? __ip_finish_output+0x217/0x380 ? srso_alias_return_thunk+0x5/0xfbef5 __ip_finish_output+0x217/0x380 ip_output+0x99/0x120 __ip_queue_xmit+0xae4/0xbc0 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? tcp_options_write.constprop.0+0xcb/0x3e0 ip_queue_xmit+0x34/0x40 __tcp_transmit_skb+0x1625/0x1890 tcp_write_xmit+0x766/0x2fb0 ? __entry_text_end+0x102ba9/0x102bad ? srso_alias_return_thunk+0x5/0xfbef5 ? __might_fault+0x74/0xc0 ? srso_alias_return_thunk+0x5/0xfbef5 __tcp_push_pending_frames+0x56/0x190 tcp_push+0x117/0x310 tcp_sendmsg_locked+0x14c1/0x1740 tcp_sendmsg+0x28/0x40 inet_sendmsg+0x5d/0x90 sock_write_iter+0x242/0x2b0 vfs_write+0x68d/0x800 ? __pfx_sock_write_iter+0x10/0x10 ksys_write+0xc8/0xf0 __x64_sys_write+0x3d/0x50 x64_sys_call+0xfaf/0x1f50 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f4d143af992 Code: c3 8b 07 85 c0 75 24 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> e9 01 cc ff ff 41 54 b8 02 00 00 0 RSP: 002b:00007ffd65032058 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f4d143af992 RDX: 0000000000000025 RSI: 00007f4d143f3bcc RDI: 0000000000000005 RBP: 00007f4d143f2b28 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4d143f3bcc R13: 0000000000000005 R14: 0000000000000000 R15: 00007ffd650323f0 </TASK> Fixes: 0b2c597 ("l2tp: close all race conditions in l2tp_tunnel_register()") Suggested-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot+6acef9e0a4d1f46c83d4@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=6acef9e0a4d1f46c83d4 CC: gnault@redhat.com CC: cong.wang@bytedance.com Signed-off-by: James Chapman <jchapman@katalix.com> Signed-off-by: Tom Parkin <tparkin@katalix.com> Link: https://patch.msgid.link/20240806160626.1248317-1-jchapman@katalix.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
ptr1337
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Aug 14, 2024
[ Upstream commit 83f4414 ] Test case: 2 threads write short inline data to a file. In ext4_page_mkwrite the resulting inline data is converted. Handling ext4_grp_locked_error with description "block bitmap and bg descriptor inconsistent: X vs Y free clusters" calls ext4_force_shutdown. The conversion clears EXT4_STATE_MAY_INLINE_DATA but fails for ext4_destroy_inline_data_nolock and ext4_mark_iloc_dirty due to ext4_forced_shutdown. The restoration of inline data fails for the same reason not setting EXT4_STATE_MAY_INLINE_DATA. Without the flag set a regular process path in ext4_da_write_end follows trying to dereference page folio private pointer that has not been set. The fix calls early return with -EIO error shall the pointer to private be NULL. Sample crash report: Unable to handle kernel paging request at virtual address dfff800000000004 KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] Mem abort info: ESR = 0x0000000096000005 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x05: level 1 translation fault Data abort info: ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [dfff800000000004] address between user and kernel address ranges Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 20274 Comm: syz-executor185 Not tainted 6.9.0-rc7-syzkaller-gfda5695d692c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : __block_commit_write+0x64/0x2b0 fs/buffer.c:2167 lr : __block_commit_write+0x3c/0x2b0 fs/buffer.c:2160 sp : ffff8000a1957600 x29: ffff8000a1957610 x28: dfff800000000000 x27: ffff0000e30e34b0 x26: 0000000000000000 x25: dfff800000000000 x24: dfff800000000000 x23: fffffdffc397c9e0 x22: 0000000000000020 x21: 0000000000000020 x20: 0000000000000040 x19: fffffdffc397c9c0 x18: 1fffe000367bd196 x17: ffff80008eead000 x16: ffff80008ae89e3c x15: 00000000200000c0 x14: 1fffe0001cbe4e04 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000001 x10: 0000000000ff0100 x9 : 0000000000000000 x8 : 0000000000000004 x7 : 0000000000000000 x6 : 0000000000000000 x5 : fffffdffc397c9c0 x4 : 0000000000000020 x3 : 0000000000000020 x2 : 0000000000000040 x1 : 0000000000000020 x0 : fffffdffc397c9c0 Call trace: __block_commit_write+0x64/0x2b0 fs/buffer.c:2167 block_write_end+0xb4/0x104 fs/buffer.c:2253 ext4_da_do_write_end fs/ext4/inode.c:2955 [inline] ext4_da_write_end+0x2c4/0xa40 fs/ext4/inode.c:3028 generic_perform_write+0x394/0x588 mm/filemap.c:3985 ext4_buffered_write_iter+0x2c0/0x4ec fs/ext4/file.c:299 ext4_file_write_iter+0x188/0x1780 call_write_iter include/linux/fs.h:2110 [inline] new_sync_write fs/read_write.c:497 [inline] vfs_write+0x968/0xc3c fs/read_write.c:590 ksys_write+0x15c/0x26c fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:652 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 Code: 97f85911 f94002da 91008356 d343fec8 (38796908) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: 97f85911 bl 0xffffffffffe16444 4: f94002da ldr x26, [x22] 8: 91008356 add x22, x26, #0x20 c: d343fec8 lsr x8, x22, #3 * 10: 38796908 ldrb w8, [x8, x25] <-- trapping instruction Reported-by: syzbot+18df508cf00a0598d9a6@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=18df508cf00a0598d9a6 Link: https://lore.kernel.org/all/000000000000f19a1406109eb5c5@google.com/T/ Signed-off-by: Wojciech Gładysz <wojciech.gladysz@infogain.com> Link: https://patch.msgid.link/20240703070112.10235-1-wojciech.gladysz@infogain.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
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Lockdep reported a warning in Linux version 6.6: [ 414.344659] ================================ [ 414.345155] WARNING: inconsistent lock state [ 414.345658] 6.6.0-07439-gba2303cacfda torvalds#6 Not tainted [ 414.346221] -------------------------------- [ 414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. [ 414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes: [ 414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0 [ 414.351204] {IN-SOFTIRQ-W} state was registered at: [ 414.351751] lock_acquire+0x18d/0x460 [ 414.352218] _raw_spin_lock_irqsave+0x39/0x60 [ 414.352769] __wake_up_common_lock+0x22/0x60 [ 414.353289] sbitmap_queue_wake_up+0x375/0x4f0 [ 414.353829] sbitmap_queue_clear+0xdd/0x270 [ 414.354338] blk_mq_put_tag+0xdf/0x170 [ 414.354807] __blk_mq_free_request+0x381/0x4d0 [ 414.355335] blk_mq_free_request+0x28b/0x3e0 [ 414.355847] __blk_mq_end_request+0x242/0xc30 [ 414.356367] scsi_end_request+0x2c1/0x830 [ 414.345155] WARNING: inconsistent lock state [ 414.345658] 6.6.0-07439-gba2303cacfda torvalds#6 Not tainted [ 414.346221] -------------------------------- [ 414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. [ 414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes: [ 414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0 [ 414.351204] {IN-SOFTIRQ-W} state was registered at: [ 414.351751] lock_acquire+0x18d/0x460 [ 414.352218] _raw_spin_lock_irqsave+0x39/0x60 [ 414.352769] __wake_up_common_lock+0x22/0x60 [ 414.353289] sbitmap_queue_wake_up+0x375/0x4f0 [ 414.353829] sbitmap_queue_clear+0xdd/0x270 [ 414.354338] blk_mq_put_tag+0xdf/0x170 [ 414.354807] __blk_mq_free_request+0x381/0x4d0 [ 414.355335] blk_mq_free_request+0x28b/0x3e0 [ 414.355847] __blk_mq_end_request+0x242/0xc30 [ 414.356367] scsi_end_request+0x2c1/0x830 [ 414.356863] scsi_io_completion+0x177/0x1610 [ 414.357379] scsi_complete+0x12f/0x260 [ 414.357856] blk_complete_reqs+0xba/0xf0 [ 414.358338] __do_softirq+0x1b0/0x7a2 [ 414.358796] irq_exit_rcu+0x14b/0x1a0 [ 414.359262] sysvec_call_function_single+0xaf/0xc0 [ 414.359828] asm_sysvec_call_function_single+0x1a/0x20 [ 414.360426] default_idle+0x1e/0x30 [ 414.360873] default_idle_call+0x9b/0x1f0 [ 414.361390] do_idle+0x2d2/0x3e0 [ 414.361819] cpu_startup_entry+0x55/0x60 [ 414.362314] start_secondary+0x235/0x2b0 [ 414.362809] secondary_startup_64_no_verify+0x18f/0x19b [ 414.363413] irq event stamp: 428794 [ 414.363825] hardirqs last enabled at (428793): [<ffffffff816bfd1c>] ktime_get+0x1dc/0x200 [ 414.364694] hardirqs last disabled at (428794): [<ffffffff85470177>] _raw_spin_lock_irq+0x47/0x50 [ 414.365629] softirqs last enabled at (428444): [<ffffffff85474780>] __do_softirq+0x540/0x7a2 [ 414.366522] softirqs last disabled at (428419): [<ffffffff813f65ab>] irq_exit_rcu+0x14b/0x1a0 [ 414.367425] other info that might help us debug this: [ 414.368194] Possible unsafe locking scenario: [ 414.368900] CPU0 [ 414.369225] ---- [ 414.369548] lock(&sbq->ws[i].wait); [ 414.370000] <Interrupt> [ 414.370342] lock(&sbq->ws[i].wait); [ 414.370802] *** DEADLOCK *** [ 414.371569] 5 locks held by kworker/u10:3/1152: [ 414.372088] #0: ffff88810130e938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x357/0x13f0 [ 414.373180] #1: ffff88810201fdb8 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x3a3/0x13f0 [ 414.374384] #2: ffffffff86ffbdc0 (rcu_read_lock){....}-{1:2}, at: blk_mq_run_hw_queue+0x637/0xa00 [ 414.375342] #3: ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0 [ 414.376377] #4: ffff888106205a08 (&hctx->dispatch_wait_lock){+.-.}-{2:2}, at: blk_mq_dispatch_rq_list+0x1337/0x1ee0 [ 414.378607] stack backtrace: [ 414.379177] CPU: 0 PID: 1152 Comm: kworker/u10:3 Not tainted 6.6.0-07439-gba2303cacfda torvalds#6 [ 414.380032] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 414.381177] Workqueue: writeback wb_workfn (flush-253:0) [ 414.381805] Call Trace: [ 414.382136] <TASK> [ 414.382429] dump_stack_lvl+0x91/0xf0 [ 414.382884] mark_lock_irq+0xb3b/0x1260 [ 414.383367] ? __pfx_mark_lock_irq+0x10/0x10 [ 414.383889] ? stack_trace_save+0x8e/0xc0 [ 414.384373] ? __pfx_stack_trace_save+0x10/0x10 [ 414.384903] ? graph_lock+0xcf/0x410 [ 414.385350] ? save_trace+0x3d/0xc70 [ 414.385808] mark_lock.part.20+0x56d/0xa90 [ 414.386317] mark_held_locks+0xb0/0x110 [ 414.386791] ? __pfx_do_raw_spin_lock+0x10/0x10 [ 414.387320] lockdep_hardirqs_on_prepare+0x297/0x3f0 [ 414.387901] ? _raw_spin_unlock_irq+0x28/0x50 [ 414.388422] trace_hardirqs_on+0x58/0x100 [ 414.388917] _raw_spin_unlock_irq+0x28/0x50 [ 414.389422] __blk_mq_tag_busy+0x1d6/0x2a0 [ 414.389920] __blk_mq_get_driver_tag+0x761/0x9f0 [ 414.390899] blk_mq_dispatch_rq_list+0x1780/0x1ee0 [ 414.391473] ? __pfx_blk_mq_dispatch_rq_list+0x10/0x10 [ 414.392070] ? sbitmap_get+0x2b8/0x450 [ 414.392533] ? __blk_mq_get_driver_tag+0x210/0x9f0 [ 414.393095] __blk_mq_sched_dispatch_requests+0xd99/0x1690 [ 414.393730] ? elv_attempt_insert_merge+0x1b1/0x420 [ 414.394302] ? __pfx___blk_mq_sched_dispatch_requests+0x10/0x10 [ 414.394970] ? lock_acquire+0x18d/0x460 [ 414.395456] ? blk_mq_run_hw_queue+0x637/0xa00 [ 414.395986] ? __pfx_lock_acquire+0x10/0x10 [ 414.396499] blk_mq_sched_dispatch_requests+0x109/0x190 [ 414.397100] blk_mq_run_hw_queue+0x66e/0xa00 [ 414.397616] blk_mq_flush_plug_list.part.17+0x614/0x2030 [ 414.398244] ? __pfx_blk_mq_flush_plug_list.part.17+0x10/0x10 [ 414.398897] ? writeback_sb_inodes+0x241/0xcc0 [ 414.399429] blk_mq_flush_plug_list+0x65/0x80 [ 414.399957] __blk_flush_plug+0x2f1/0x530 [ 414.400458] ? __pfx___blk_flush_plug+0x10/0x10 [ 414.400999] blk_finish_plug+0x59/0xa0 [ 414.401467] wb_writeback+0x7cc/0x920 [ 414.401935] ? __pfx_wb_writeback+0x10/0x10 [ 414.402442] ? mark_held_locks+0xb0/0x110 [ 414.402931] ? __pfx_do_raw_spin_lock+0x10/0x10 [ 414.403462] ? lockdep_hardirqs_on_prepare+0x297/0x3f0 [ 414.404062] wb_workfn+0x2b3/0xcf0 [ 414.404500] ? __pfx_wb_workfn+0x10/0x10 [ 414.404989] process_scheduled_works+0x432/0x13f0 [ 414.405546] ? __pfx_process_scheduled_works+0x10/0x10 [ 414.406139] ? do_raw_spin_lock+0x101/0x2a0 [ 414.406641] ? assign_work+0x19b/0x240 [ 414.407106] ? lock_is_held_type+0x9d/0x110 [ 414.407604] worker_thread+0x6f2/0x1160 [ 414.408075] ? __kthread_parkme+0x62/0x210 [ 414.408572] ? lockdep_hardirqs_on_prepare+0x297/0x3f0 [ 414.409168] ? __kthread_parkme+0x13c/0x210 [ 414.409678] ? __pfx_worker_thread+0x10/0x10 [ 414.410191] kthread+0x33c/0x440 [ 414.410602] ? __pfx_kthread+0x10/0x10 [ 414.411068] ret_from_fork+0x4d/0x80 [ 414.411526] ? __pfx_kthread+0x10/0x10 [ 414.411993] ret_from_fork_asm+0x1b/0x30 [ 414.412489] </TASK> When interrupt is turned on while a lock holding by spin_lock_irq it throws a warning because of potential deadlock. blk_mq_prep_dispatch_rq blk_mq_get_driver_tag __blk_mq_get_driver_tag __blk_mq_alloc_driver_tag blk_mq_tag_busy -> tag is already busy // failed to get driver tag blk_mq_mark_tag_wait spin_lock_irq(&wq->lock) -> lock A (&sbq->ws[i].wait) __add_wait_queue(wq, wait) -> wait queue active blk_mq_get_driver_tag __blk_mq_tag_busy -> 1) tag must be idle, which means there can't be inflight IO spin_lock_irq(&tags->lock) -> lock B (hctx->tags) spin_unlock_irq(&tags->lock) -> unlock B, turn on interrupt accidentally -> 2) context must be preempt by IO interrupt to trigger deadlock. As shown above, the deadlock is not possible in theory, but the warning still need to be fixed. Fix it by using spin_lock_irqsave to get lockB instead of spin_lock_irq. Fixes: 4f1731d ("blk-mq: fix potential io hang by wrong 'wake_batch'") Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20240815024736.2040971-1-lilingfeng@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
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…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 disable BH when collecting stats via hardware offload to ensure concurrent updates from packet path do not result in losing stats. From Sebastian Andrzej Siewior. Patch #2 uses write seqcount to reset counters serialize against reader. Also from Sebastian Andrzej Siewior. Patch #3 ensures vlan header is in place before accessing its fields, according to KMSAN splat triggered by syzbot. * tag 'nf-24-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: flowtable: validate vlan header netfilter: nft_counter: Synchronize nft_counter_reset() against reader. netfilter: nft_counter: Disable BH in nft_counter_offload_stats(). ==================== Link: https://patch.msgid.link/20240822101842.4234-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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[ Upstream commit b313a8c ] Lockdep reported a warning in Linux version 6.6: [ 414.344659] ================================ [ 414.345155] WARNING: inconsistent lock state [ 414.345658] 6.6.0-07439-gba2303cacfda torvalds#6 Not tainted [ 414.346221] -------------------------------- [ 414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. [ 414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes: [ 414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0 [ 414.351204] {IN-SOFTIRQ-W} state was registered at: [ 414.351751] lock_acquire+0x18d/0x460 [ 414.352218] _raw_spin_lock_irqsave+0x39/0x60 [ 414.352769] __wake_up_common_lock+0x22/0x60 [ 414.353289] sbitmap_queue_wake_up+0x375/0x4f0 [ 414.353829] sbitmap_queue_clear+0xdd/0x270 [ 414.354338] blk_mq_put_tag+0xdf/0x170 [ 414.354807] __blk_mq_free_request+0x381/0x4d0 [ 414.355335] blk_mq_free_request+0x28b/0x3e0 [ 414.355847] __blk_mq_end_request+0x242/0xc30 [ 414.356367] scsi_end_request+0x2c1/0x830 [ 414.345155] WARNING: inconsistent lock state [ 414.345658] 6.6.0-07439-gba2303cacfda torvalds#6 Not tainted [ 414.346221] -------------------------------- [ 414.346712] inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. [ 414.347545] kworker/u10:3/1152 [HC0[0]:SC0[0]:HE0:SE1] takes: [ 414.349245] ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0 [ 414.351204] {IN-SOFTIRQ-W} state was registered at: [ 414.351751] lock_acquire+0x18d/0x460 [ 414.352218] _raw_spin_lock_irqsave+0x39/0x60 [ 414.352769] __wake_up_common_lock+0x22/0x60 [ 414.353289] sbitmap_queue_wake_up+0x375/0x4f0 [ 414.353829] sbitmap_queue_clear+0xdd/0x270 [ 414.354338] blk_mq_put_tag+0xdf/0x170 [ 414.354807] __blk_mq_free_request+0x381/0x4d0 [ 414.355335] blk_mq_free_request+0x28b/0x3e0 [ 414.355847] __blk_mq_end_request+0x242/0xc30 [ 414.356367] scsi_end_request+0x2c1/0x830 [ 414.356863] scsi_io_completion+0x177/0x1610 [ 414.357379] scsi_complete+0x12f/0x260 [ 414.357856] blk_complete_reqs+0xba/0xf0 [ 414.358338] __do_softirq+0x1b0/0x7a2 [ 414.358796] irq_exit_rcu+0x14b/0x1a0 [ 414.359262] sysvec_call_function_single+0xaf/0xc0 [ 414.359828] asm_sysvec_call_function_single+0x1a/0x20 [ 414.360426] default_idle+0x1e/0x30 [ 414.360873] default_idle_call+0x9b/0x1f0 [ 414.361390] do_idle+0x2d2/0x3e0 [ 414.361819] cpu_startup_entry+0x55/0x60 [ 414.362314] start_secondary+0x235/0x2b0 [ 414.362809] secondary_startup_64_no_verify+0x18f/0x19b [ 414.363413] irq event stamp: 428794 [ 414.363825] hardirqs last enabled at (428793): [<ffffffff816bfd1c>] ktime_get+0x1dc/0x200 [ 414.364694] hardirqs last disabled at (428794): [<ffffffff85470177>] _raw_spin_lock_irq+0x47/0x50 [ 414.365629] softirqs last enabled at (428444): [<ffffffff85474780>] __do_softirq+0x540/0x7a2 [ 414.366522] softirqs last disabled at (428419): [<ffffffff813f65ab>] irq_exit_rcu+0x14b/0x1a0 [ 414.367425] other info that might help us debug this: [ 414.368194] Possible unsafe locking scenario: [ 414.368900] CPU0 [ 414.369225] ---- [ 414.369548] lock(&sbq->ws[i].wait); [ 414.370000] <Interrupt> [ 414.370342] lock(&sbq->ws[i].wait); [ 414.370802] *** DEADLOCK *** [ 414.371569] 5 locks held by kworker/u10:3/1152: [ 414.372088] #0: ffff88810130e938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x357/0x13f0 [ 414.373180] #1: ffff88810201fdb8 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x3a3/0x13f0 [ 414.374384] #2: ffffffff86ffbdc0 (rcu_read_lock){....}-{1:2}, at: blk_mq_run_hw_queue+0x637/0xa00 [ 414.375342] #3: ffff88810edd1098 (&sbq->ws[i].wait){+.?.}-{2:2}, at: blk_mq_dispatch_rq_list+0x131c/0x1ee0 [ 414.376377] #4: ffff888106205a08 (&hctx->dispatch_wait_lock){+.-.}-{2:2}, at: blk_mq_dispatch_rq_list+0x1337/0x1ee0 [ 414.378607] stack backtrace: [ 414.379177] CPU: 0 PID: 1152 Comm: kworker/u10:3 Not tainted 6.6.0-07439-gba2303cacfda torvalds#6 [ 414.380032] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 414.381177] Workqueue: writeback wb_workfn (flush-253:0) [ 414.381805] Call Trace: [ 414.382136] <TASK> [ 414.382429] dump_stack_lvl+0x91/0xf0 [ 414.382884] mark_lock_irq+0xb3b/0x1260 [ 414.383367] ? __pfx_mark_lock_irq+0x10/0x10 [ 414.383889] ? stack_trace_save+0x8e/0xc0 [ 414.384373] ? __pfx_stack_trace_save+0x10/0x10 [ 414.384903] ? graph_lock+0xcf/0x410 [ 414.385350] ? save_trace+0x3d/0xc70 [ 414.385808] mark_lock.part.20+0x56d/0xa90 [ 414.386317] mark_held_locks+0xb0/0x110 [ 414.386791] ? __pfx_do_raw_spin_lock+0x10/0x10 [ 414.387320] lockdep_hardirqs_on_prepare+0x297/0x3f0 [ 414.387901] ? _raw_spin_unlock_irq+0x28/0x50 [ 414.388422] trace_hardirqs_on+0x58/0x100 [ 414.388917] _raw_spin_unlock_irq+0x28/0x50 [ 414.389422] __blk_mq_tag_busy+0x1d6/0x2a0 [ 414.389920] __blk_mq_get_driver_tag+0x761/0x9f0 [ 414.390899] blk_mq_dispatch_rq_list+0x1780/0x1ee0 [ 414.391473] ? __pfx_blk_mq_dispatch_rq_list+0x10/0x10 [ 414.392070] ? sbitmap_get+0x2b8/0x450 [ 414.392533] ? __blk_mq_get_driver_tag+0x210/0x9f0 [ 414.393095] __blk_mq_sched_dispatch_requests+0xd99/0x1690 [ 414.393730] ? elv_attempt_insert_merge+0x1b1/0x420 [ 414.394302] ? __pfx___blk_mq_sched_dispatch_requests+0x10/0x10 [ 414.394970] ? lock_acquire+0x18d/0x460 [ 414.395456] ? blk_mq_run_hw_queue+0x637/0xa00 [ 414.395986] ? __pfx_lock_acquire+0x10/0x10 [ 414.396499] blk_mq_sched_dispatch_requests+0x109/0x190 [ 414.397100] blk_mq_run_hw_queue+0x66e/0xa00 [ 414.397616] blk_mq_flush_plug_list.part.17+0x614/0x2030 [ 414.398244] ? __pfx_blk_mq_flush_plug_list.part.17+0x10/0x10 [ 414.398897] ? writeback_sb_inodes+0x241/0xcc0 [ 414.399429] blk_mq_flush_plug_list+0x65/0x80 [ 414.399957] __blk_flush_plug+0x2f1/0x530 [ 414.400458] ? __pfx___blk_flush_plug+0x10/0x10 [ 414.400999] blk_finish_plug+0x59/0xa0 [ 414.401467] wb_writeback+0x7cc/0x920 [ 414.401935] ? __pfx_wb_writeback+0x10/0x10 [ 414.402442] ? mark_held_locks+0xb0/0x110 [ 414.402931] ? __pfx_do_raw_spin_lock+0x10/0x10 [ 414.403462] ? lockdep_hardirqs_on_prepare+0x297/0x3f0 [ 414.404062] wb_workfn+0x2b3/0xcf0 [ 414.404500] ? __pfx_wb_workfn+0x10/0x10 [ 414.404989] process_scheduled_works+0x432/0x13f0 [ 414.405546] ? __pfx_process_scheduled_works+0x10/0x10 [ 414.406139] ? do_raw_spin_lock+0x101/0x2a0 [ 414.406641] ? assign_work+0x19b/0x240 [ 414.407106] ? lock_is_held_type+0x9d/0x110 [ 414.407604] worker_thread+0x6f2/0x1160 [ 414.408075] ? __kthread_parkme+0x62/0x210 [ 414.408572] ? lockdep_hardirqs_on_prepare+0x297/0x3f0 [ 414.409168] ? __kthread_parkme+0x13c/0x210 [ 414.409678] ? __pfx_worker_thread+0x10/0x10 [ 414.410191] kthread+0x33c/0x440 [ 414.410602] ? __pfx_kthread+0x10/0x10 [ 414.411068] ret_from_fork+0x4d/0x80 [ 414.411526] ? __pfx_kthread+0x10/0x10 [ 414.411993] ret_from_fork_asm+0x1b/0x30 [ 414.412489] </TASK> When interrupt is turned on while a lock holding by spin_lock_irq it throws a warning because of potential deadlock. blk_mq_prep_dispatch_rq blk_mq_get_driver_tag __blk_mq_get_driver_tag __blk_mq_alloc_driver_tag blk_mq_tag_busy -> tag is already busy // failed to get driver tag blk_mq_mark_tag_wait spin_lock_irq(&wq->lock) -> lock A (&sbq->ws[i].wait) __add_wait_queue(wq, wait) -> wait queue active blk_mq_get_driver_tag __blk_mq_tag_busy -> 1) tag must be idle, which means there can't be inflight IO spin_lock_irq(&tags->lock) -> lock B (hctx->tags) spin_unlock_irq(&tags->lock) -> unlock B, turn on interrupt accidentally -> 2) context must be preempt by IO interrupt to trigger deadlock. As shown above, the deadlock is not possible in theory, but the warning still need to be fixed. Fix it by using spin_lock_irqsave to get lockB instead of spin_lock_irq. Fixes: 4f1731d ("blk-mq: fix potential io hang by wrong 'wake_batch'") Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20240815024736.2040971-1-lilingfeng@huaweicloud.com Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
ptr1337
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Sep 12, 2024
[ Upstream commit c3a5e3e ] When using cachefiles, lockdep may emit something similar to the circular locking dependency notice below. The problem appears to stem from the following: (1) Cachefiles manipulates xattrs on the files in its cache when called from ->writepages(). (2) The setxattr() and removexattr() system call handlers get the name (and value) from userspace after taking the sb_writers lock, putting accesses of the vma->vm_lock and mm->mmap_lock inside of that. (3) The afs filesystem uses a per-inode lock to prevent multiple revalidation RPCs and in writeback vs truncate to prevent parallel operations from deadlocking against the server on one side and local page locks on the other. Fix this by moving the getting of the name and value in {get,remove}xattr() outside of the sb_writers lock. This also has the minor benefits that we don't need to reget these in the event of a retry and we never try to take the sb_writers lock in the event we can't pull the name and value into the kernel. Alternative approaches that might fix this include moving the dispatch of a write to the cache off to a workqueue or trying to do without the validation lock in afs. Note that this might also affect other filesystems that use netfslib and/or cachefiles. ====================================================== WARNING: possible circular locking dependency detected 6.10.0-build2+ torvalds#956 Not tainted ------------------------------------------------------ fsstress/6050 is trying to acquire lock: ffff888138fd82f0 (mapping.invalidate_lock#3){++++}-{3:3}, at: filemap_fault+0x26e/0x8b0 but task is already holding lock: ffff888113f26d18 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x165/0x250 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&vma->vm_lock->lock){++++}-{3:3}: __lock_acquire+0xaf0/0xd80 lock_acquire.part.0+0x103/0x280 down_write+0x3b/0x50 vma_start_write+0x6b/0xa0 vma_link+0xcc/0x140 insert_vm_struct+0xb7/0xf0 alloc_bprm+0x2c1/0x390 kernel_execve+0x65/0x1a0 call_usermodehelper_exec_async+0x14d/0x190 ret_from_fork+0x24/0x40 ret_from_fork_asm+0x1a/0x30 -> #3 (&mm->mmap_lock){++++}-{3:3}: __lock_acquire+0xaf0/0xd80 lock_acquire.part.0+0x103/0x280 __might_fault+0x7c/0xb0 strncpy_from_user+0x25/0x160 removexattr+0x7f/0x100 __do_sys_fremovexattr+0x7e/0xb0 do_syscall_64+0x9f/0x100 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #2 (sb_writers#14){.+.+}-{0:0}: __lock_acquire+0xaf0/0xd80 lock_acquire.part.0+0x103/0x280 percpu_down_read+0x3c/0x90 vfs_iocb_iter_write+0xe9/0x1d0 __cachefiles_write+0x367/0x430 cachefiles_issue_write+0x299/0x2f0 netfs_advance_write+0x117/0x140 netfs_write_folio.isra.0+0x5ca/0x6e0 netfs_writepages+0x230/0x2f0 afs_writepages+0x4d/0x70 do_writepages+0x1e8/0x3e0 filemap_fdatawrite_wbc+0x84/0xa0 __filemap_fdatawrite_range+0xa8/0xf0 file_write_and_wait_range+0x59/0x90 afs_release+0x10f/0x270 __fput+0x25f/0x3d0 __do_sys_close+0x43/0x70 do_syscall_64+0x9f/0x100 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (&vnode->validate_lock){++++}-{3:3}: __lock_acquire+0xaf0/0xd80 lock_acquire.part.0+0x103/0x280 down_read+0x95/0x200 afs_writepages+0x37/0x70 do_writepages+0x1e8/0x3e0 filemap_fdatawrite_wbc+0x84/0xa0 filemap_invalidate_inode+0x167/0x1e0 netfs_unbuffered_write_iter+0x1bd/0x2d0 vfs_write+0x22e/0x320 ksys_write+0xbc/0x130 do_syscall_64+0x9f/0x100 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #0 (mapping.invalidate_lock#3){++++}-{3:3}: check_noncircular+0x119/0x160 check_prev_add+0x195/0x430 __lock_acquire+0xaf0/0xd80 lock_acquire.part.0+0x103/0x280 down_read+0x95/0x200 filemap_fault+0x26e/0x8b0 __do_fault+0x57/0xd0 do_pte_missing+0x23b/0x320 __handle_mm_fault+0x2d4/0x320 handle_mm_fault+0x14f/0x260 do_user_addr_fault+0x2a2/0x500 exc_page_fault+0x71/0x90 asm_exc_page_fault+0x22/0x30 other info that might help us debug this: Chain exists of: mapping.invalidate_lock#3 --> &mm->mmap_lock --> &vma->vm_lock->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(&vma->vm_lock->lock); lock(&mm->mmap_lock); lock(&vma->vm_lock->lock); rlock(mapping.invalidate_lock#3); *** DEADLOCK *** 1 lock held by fsstress/6050: #0: ffff888113f26d18 (&vma->vm_lock->lock){++++}-{3:3}, at: lock_vma_under_rcu+0x165/0x250 stack backtrace: CPU: 0 PID: 6050 Comm: fsstress Not tainted 6.10.0-build2+ torvalds#956 Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014 Call Trace: <TASK> dump_stack_lvl+0x57/0x80 check_noncircular+0x119/0x160 ? queued_spin_lock_slowpath+0x4be/0x510 ? __pfx_check_noncircular+0x10/0x10 ? __pfx_queued_spin_lock_slowpath+0x10/0x10 ? mark_lock+0x47/0x160 ? init_chain_block+0x9c/0xc0 ? add_chain_block+0x84/0xf0 check_prev_add+0x195/0x430 __lock_acquire+0xaf0/0xd80 ? __pfx___lock_acquire+0x10/0x10 ? __lock_release.isra.0+0x13b/0x230 lock_acquire.part.0+0x103/0x280 ? filemap_fault+0x26e/0x8b0 ? __pfx_lock_acquire.part.0+0x10/0x10 ? rcu_is_watching+0x34/0x60 ? lock_acquire+0xd7/0x120 down_read+0x95/0x200 ? filemap_fault+0x26e/0x8b0 ? __pfx_down_read+0x10/0x10 ? __filemap_get_folio+0x25/0x1a0 filemap_fault+0x26e/0x8b0 ? __pfx_filemap_fault+0x10/0x10 ? find_held_lock+0x7c/0x90 ? __pfx___lock_release.isra.0+0x10/0x10 ? __pte_offset_map+0x99/0x110 __do_fault+0x57/0xd0 do_pte_missing+0x23b/0x320 __handle_mm_fault+0x2d4/0x320 ? __pfx___handle_mm_fault+0x10/0x10 handle_mm_fault+0x14f/0x260 do_user_addr_fault+0x2a2/0x500 exc_page_fault+0x71/0x90 asm_exc_page_fault+0x22/0x30 Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/2136178.1721725194@warthog.procyon.org.uk cc: Alexander Viro <viro@zeniv.linux.org.uk> cc: Christian Brauner <brauner@kernel.org> cc: Jan Kara <jack@suse.cz> cc: Jeff Layton <jlayton@kernel.org> cc: Gao Xiang <xiang@kernel.org> cc: Matthew Wilcox <willy@infradead.org> cc: netfs@lists.linux.dev cc: linux-erofs@lists.ozlabs.org cc: linux-fsdevel@vger.kernel.org [brauner: fix minor issues] Signed-off-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
1Naim
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Sep 25, 2024
Once the kthread is running and available
(i.e. @printk_kthreads_running is set), the kthread becomes
responsible for flushing any pending messages which are added
in NBCON_PRIO_NORMAL context. Namely the legacy
console_flush_all() and device_release() no longer flush the
console. And nbcon_atomic_flush_pending() used by
nbcon_cpu_emergency_exit() no longer flushes messages added
after the emergency messages.
The console context is safe when used by the kthread only when
one of the following conditions are true:
1. Other caller acquires the console context with
NBCON_PRIO_NORMAL with preemption disabled. It will
release the context before rescheduling.
2. Other caller acquires the console context with
NBCON_PRIO_NORMAL under the device_lock.
3. The kthread is the only context which acquires the console
with NBCON_PRIO_NORMAL.
This is satisfied for all atomic printing call sites:
nbcon_legacy_emit_next_record() (#1)
nbcon_atomic_flush_pending_con() (#1)
nbcon_device_release() (#2)
It is even double guaranteed when @printk_kthreads_running
is set because then _only_ the kthread will print for
NBCON_PRIO_NORMAL. (#3)
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20240904120536.115780-10-john.ogness@linutronix.de
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Eric Naim <dnaim@cachyos.org>
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