Rust unstable features needed for the kernel #2
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ojeda
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Allocating memory with regulator_list_mutex held makes lockdep unhappy when memory pressure makes the system do fs_reclaim on eg. eMMC using a regulator. Push the lock inside regulator_init_coupling() after the allocation. ====================================================== WARNING: possible circular locking dependency detected 5.7.13+ #533 Not tainted ------------------------------------------------------ kswapd0/383 is trying to acquire lock: cca78ca4 (&sbi->write_io[i][j].io_rwsem){++++}-{3:3}, at: __submit_merged_write_cond+0x104/0x154 but task is already holding lock: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire.part.11+0x40/0x50 fs_reclaim_acquire+0x24/0x28 __kmalloc+0x54/0x218 regulator_register+0x860/0x1584 dummy_regulator_probe+0x60/0xa8 [...] other info that might help us debug this: Chain exists of: &sbi->write_io[i][j].io_rwsem --> regulator_list_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(regulator_list_mutex); lock(fs_reclaim); lock(&sbi->write_io[i][j].io_rwsem); *** DEADLOCK *** 1 lock held by kswapd0/383: #0: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50 [...] Fixes: d8ca7d1 ("regulator: core: Introduce API for regulators coupling customization") Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/1a889cf7f61c6429c9e6b34ddcdde99be77a26b6.1597195321.git.mirq-linux@rere.qmqm.pl Signed-off-by: Mark Brown <broonie@kernel.org>
ojeda
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With the conversion of the tree locks to rwsem I got the following lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc7-00165-g04ec4da5f45f-dirty #922 Not tainted ------------------------------------------------------ compsize/11122 is trying to acquire lock: ffff889fabca8768 (&mm->mmap_lock#2){++++}-{3:3}, at: __might_fault+0x3e/0x90 but task is already holding lock: ffff889fe720fe40 (btrfs-fs-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x39/0x180 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (btrfs-fs-00){++++}-{3:3}: down_write_nested+0x3b/0x70 __btrfs_tree_lock+0x24/0x120 btrfs_search_slot+0x756/0x990 btrfs_lookup_inode+0x3a/0xb4 __btrfs_update_delayed_inode+0x93/0x270 btrfs_async_run_delayed_root+0x168/0x230 btrfs_work_helper+0xd4/0x570 process_one_work+0x2ad/0x5f0 worker_thread+0x3a/0x3d0 kthread+0x133/0x150 ret_from_fork+0x1f/0x30 -> #1 (&delayed_node->mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_delayed_update_inode+0x50/0x440 btrfs_update_inode+0x8a/0xf0 btrfs_dirty_inode+0x5b/0xd0 touch_atime+0xa1/0xd0 btrfs_file_mmap+0x3f/0x60 mmap_region+0x3a4/0x640 do_mmap+0x376/0x580 vm_mmap_pgoff+0xd5/0x120 ksys_mmap_pgoff+0x193/0x230 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&mm->mmap_lock#2){++++}-{3:3}: __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 __might_fault+0x68/0x90 _copy_to_user+0x1e/0x80 copy_to_sk.isra.32+0x121/0x300 search_ioctl+0x106/0x200 btrfs_ioctl_tree_search_v2+0x7b/0xf0 btrfs_ioctl+0x106f/0x30a0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Chain exists of: &mm->mmap_lock#2 --> &delayed_node->mutex --> btrfs-fs-00 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(btrfs-fs-00); lock(&delayed_node->mutex); lock(btrfs-fs-00); lock(&mm->mmap_lock#2); *** DEADLOCK *** 1 lock held by compsize/11122: #0: ffff889fe720fe40 (btrfs-fs-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x39/0x180 stack backtrace: CPU: 17 PID: 11122 Comm: compsize Kdump: loaded Not tainted 5.8.0-rc7-00165-g04ec4da5f45f-dirty #922 Hardware name: Quanta Tioga Pass Single Side 01-0030993006/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018 Call Trace: dump_stack+0x78/0xa0 check_noncircular+0x165/0x180 __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 ? __might_fault+0x3e/0x90 ? find_held_lock+0x72/0x90 __might_fault+0x68/0x90 ? __might_fault+0x3e/0x90 _copy_to_user+0x1e/0x80 copy_to_sk.isra.32+0x121/0x300 ? btrfs_search_forward+0x2a6/0x360 search_ioctl+0x106/0x200 btrfs_ioctl_tree_search_v2+0x7b/0xf0 btrfs_ioctl+0x106f/0x30a0 ? __do_sys_newfstat+0x5a/0x70 ? ksys_ioctl+0x83/0xc0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The problem is we're doing a copy_to_user() while holding tree locks, which can deadlock if we have to do a page fault for the copy_to_user(). This exists even without my locking changes, so it needs to be fixed. Rework the search ioctl to do the pre-fault and then copy_to_user_nofault for the copying. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
ojeda
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I got the following lockdep splat while testing: ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc7-00172-g021118712e59 #932 Not tainted ------------------------------------------------------ btrfs/229626 is trying to acquire lock: ffffffff828513f0 (cpu_hotplug_lock){++++}-{0:0}, at: alloc_workqueue+0x378/0x450 but task is already holding lock: ffff889dd3889518 (&fs_info->scrub_lock){+.+.}-{3:3}, at: btrfs_scrub_dev+0x11c/0x630 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #7 (&fs_info->scrub_lock){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_scrub_dev+0x11c/0x630 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4 btrfs_ioctl+0x2799/0x30a0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #6 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_run_dev_stats+0x49/0x480 commit_cowonly_roots+0xb5/0x2a0 btrfs_commit_transaction+0x516/0xa60 sync_filesystem+0x6b/0x90 generic_shutdown_super+0x22/0x100 kill_anon_super+0xe/0x30 btrfs_kill_super+0x12/0x20 deactivate_locked_super+0x29/0x60 cleanup_mnt+0xb8/0x140 task_work_run+0x6d/0xb0 __prepare_exit_to_usermode+0x1cc/0x1e0 do_syscall_64+0x5c/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #5 (&fs_info->tree_log_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_commit_transaction+0x4bb/0xa60 sync_filesystem+0x6b/0x90 generic_shutdown_super+0x22/0x100 kill_anon_super+0xe/0x30 btrfs_kill_super+0x12/0x20 deactivate_locked_super+0x29/0x60 cleanup_mnt+0xb8/0x140 task_work_run+0x6d/0xb0 __prepare_exit_to_usermode+0x1cc/0x1e0 do_syscall_64+0x5c/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #4 (&fs_info->reloc_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 btrfs_record_root_in_trans+0x43/0x70 start_transaction+0xd1/0x5d0 btrfs_dirty_inode+0x42/0xd0 touch_atime+0xa1/0xd0 btrfs_file_mmap+0x3f/0x60 mmap_region+0x3a4/0x640 do_mmap+0x376/0x580 vm_mmap_pgoff+0xd5/0x120 ksys_mmap_pgoff+0x193/0x230 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #3 (&mm->mmap_lock#2){++++}-{3:3}: __might_fault+0x68/0x90 _copy_to_user+0x1e/0x80 perf_read+0x141/0x2c0 vfs_read+0xad/0x1b0 ksys_read+0x5f/0xe0 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #2 (&cpuctx_mutex){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 perf_event_init_cpu+0x88/0x150 perf_event_init+0x1db/0x20b start_kernel+0x3ae/0x53c secondary_startup_64+0xa4/0xb0 -> #1 (pmus_lock){+.+.}-{3:3}: __mutex_lock+0x9f/0x930 perf_event_init_cpu+0x4f/0x150 cpuhp_invoke_callback+0xb1/0x900 _cpu_up.constprop.26+0x9f/0x130 cpu_up+0x7b/0xc0 bringup_nonboot_cpus+0x4f/0x60 smp_init+0x26/0x71 kernel_init_freeable+0x110/0x258 kernel_init+0xa/0x103 ret_from_fork+0x1f/0x30 -> #0 (cpu_hotplug_lock){++++}-{0:0}: __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 cpus_read_lock+0x39/0xb0 alloc_workqueue+0x378/0x450 __btrfs_alloc_workqueue+0x15d/0x200 btrfs_alloc_workqueue+0x51/0x160 scrub_workers_get+0x5a/0x170 btrfs_scrub_dev+0x18c/0x630 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4 btrfs_ioctl+0x2799/0x30a0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Chain exists of: cpu_hotplug_lock --> &fs_devs->device_list_mutex --> &fs_info->scrub_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_info->scrub_lock); lock(&fs_devs->device_list_mutex); lock(&fs_info->scrub_lock); lock(cpu_hotplug_lock); *** DEADLOCK *** 2 locks held by btrfs/229626: #0: ffff88bfe8bb86e0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: btrfs_scrub_dev+0xbd/0x630 #1: ffff889dd3889518 (&fs_info->scrub_lock){+.+.}-{3:3}, at: btrfs_scrub_dev+0x11c/0x630 stack backtrace: CPU: 15 PID: 229626 Comm: btrfs Kdump: loaded Not tainted 5.8.0-rc7-00172-g021118712e59 #932 Hardware name: Quanta Tioga Pass Single Side 01-0030993006/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018 Call Trace: dump_stack+0x78/0xa0 check_noncircular+0x165/0x180 __lock_acquire+0x1272/0x2310 lock_acquire+0x9e/0x360 ? alloc_workqueue+0x378/0x450 cpus_read_lock+0x39/0xb0 ? alloc_workqueue+0x378/0x450 alloc_workqueue+0x378/0x450 ? rcu_read_lock_sched_held+0x52/0x80 __btrfs_alloc_workqueue+0x15d/0x200 btrfs_alloc_workqueue+0x51/0x160 scrub_workers_get+0x5a/0x170 btrfs_scrub_dev+0x18c/0x630 ? start_transaction+0xd1/0x5d0 btrfs_dev_replace_by_ioctl.cold.21+0x10a/0x1d4 btrfs_ioctl+0x2799/0x30a0 ? do_sigaction+0x102/0x250 ? lockdep_hardirqs_on_prepare+0xca/0x160 ? _raw_spin_unlock_irq+0x24/0x30 ? trace_hardirqs_on+0x1c/0xe0 ? _raw_spin_unlock_irq+0x24/0x30 ? do_sigaction+0x102/0x250 ? ksys_ioctl+0x83/0xc0 ksys_ioctl+0x83/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This happens because we're allocating the scrub workqueues under the scrub and device list mutex, which brings in a whole host of other dependencies. Because the work queue allocation is done with GFP_KERNEL, it can trigger reclaim, which can lead to a transaction commit, which in turns needs the device_list_mutex, it can lead to a deadlock. A different problem for which this fix is a solution. Fix this by moving the actual allocation outside of the scrub lock, and then only take the lock once we're ready to actually assign them to the fs_info. We'll now have to cleanup the workqueues in a few more places, so I've added a helper to do the refcount dance to safely free the workqueues. CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
ojeda
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…emory If the hypervisor doesn't support hugepages, the kernel ends up allocating a large number of page table pages. The early page table allocation was wrongly setting the max memblock limit to ppc64_rma_size with radix translation which resulted in boot failure as shown below. Kernel panic - not syncing: early_alloc_pgtable: Failed to allocate 16777216 bytes align=0x1000000 nid=-1 from=0x0000000000000000 max_addr=0xffffffffffffffff CPU: 0 PID: 0 Comm: swapper Not tainted 5.8.0-24.9-default+ #2 Call Trace: [c0000000016f3d00] [c0000000007c6470] dump_stack+0xc4/0x114 (unreliable) [c0000000016f3d40] [c00000000014c78c] panic+0x164/0x418 [c0000000016f3dd0] [c000000000098890] early_alloc_pgtable+0xe0/0xec [c0000000016f3e60] [c0000000010a5440] radix__early_init_mmu+0x360/0x4b4 [c0000000016f3ef0] [c000000001099bac] early_init_mmu+0x1c/0x3c [c0000000016f3f10] [c00000000109a320] early_setup+0x134/0x170 This was because the kernel was checking for the radix feature before we enable the feature via mmu_features. This resulted in the kernel using hash restrictions on radix. Rework the early init code such that the kernel boot with memblock restrictions as imposed by hash. At that point, the kernel still hasn't finalized the translation the kernel will end up using. We have three different ways of detecting radix. 1. dt_cpu_ftrs_scan -> used only in case of PowerNV 2. ibm,pa-features -> Used when we don't use cpu_dt_ftr_scan 3. CAS -> Where we negotiate with hypervisor about the supported translation. We look at 1 or 2 early in the boot and after that, we look at the CAS vector to finalize the translation the kernel will use. We also support a kernel command line option (disable_radix) to switch to hash. Update the memblock limit after mmu_early_init_devtree() if the kernel is going to use radix translation. This forces some of the memblock allocations we do before mmu_early_init_devtree() to be within the RMA limit. Fixes: 2bfd65e ("powerpc/mm/radix: Add radix callbacks for early init routines") Reported-by: Shirisha Ganta <shiganta@in.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reviewed-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200828100852.426575-1-aneesh.kumar@linux.ibm.com
ojeda
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…s metrics" test Linux 5.9 introduced perf test case "Parse and process metrics" and on s390 this test case always dumps core: [root@t35lp67 perf]# ./perf test -vvvv -F 67 67: Parse and process metrics : --- start --- metric expr inst_retired.any / cpu_clk_unhalted.thread for IPC parsing metric: inst_retired.any / cpu_clk_unhalted.thread Segmentation fault (core dumped) [root@t35lp67 perf]# I debugged this core dump and gdb shows this call chain: (gdb) where #0 0x000003ffabc3192a in __strnlen_c_1 () from /lib64/libc.so.6 #1 0x000003ffabc293de in strcasestr () from /lib64/libc.so.6 #2 0x0000000001102ba2 in match_metric(list=0x1e6ea20 "inst_retired.any", n=<optimized out>) at util/metricgroup.c:368 #3 find_metric (map=<optimized out>, map=<optimized out>, metric=0x1e6ea20 "inst_retired.any") at util/metricgroup.c:765 #4 __resolve_metric (ids=0x0, map=<optimized out>, metric_list=0x0, metric_no_group=<optimized out>, m=<optimized out>) at util/metricgroup.c:844 #5 resolve_metric (ids=0x0, map=0x0, metric_list=0x0, metric_no_group=<optimized out>) at util/metricgroup.c:881 #6 metricgroup__add_metric (metric=<optimized out>, metric_no_group=metric_no_group@entry=false, events=<optimized out>, events@entry=0x3ffd84fb878, metric_list=0x0, metric_list@entry=0x3ffd84fb868, map=0x0) at util/metricgroup.c:943 #7 0x00000000011034ae in metricgroup__add_metric_list (map=0x13f9828 <map>, metric_list=0x3ffd84fb868, events=0x3ffd84fb878, metric_no_group=<optimized out>, list=<optimized out>) at util/metricgroup.c:988 #8 parse_groups (perf_evlist=perf_evlist@entry=0x1e70260, str=str@entry=0x12f34b2 "IPC", metric_no_group=<optimized out>, metric_no_merge=<optimized out>, fake_pmu=fake_pmu@entry=0x1462f18 <perf_pmu.fake>, metric_events=0x3ffd84fba58, map=0x1) at util/metricgroup.c:1040 #9 0x0000000001103eb2 in metricgroup__parse_groups_test( evlist=evlist@entry=0x1e70260, map=map@entry=0x13f9828 <map>, str=str@entry=0x12f34b2 "IPC", metric_no_group=metric_no_group@entry=false, metric_no_merge=metric_no_merge@entry=false, metric_events=0x3ffd84fba58) at util/metricgroup.c:1082 #10 0x00000000010c84d8 in __compute_metric (ratio2=0x0, name2=0x0, ratio1=<synthetic pointer>, name1=0x12f34b2 "IPC", vals=0x3ffd84fbad8, name=0x12f34b2 "IPC") at tests/parse-metric.c:159 #11 compute_metric (ratio=<synthetic pointer>, vals=0x3ffd84fbad8, name=0x12f34b2 "IPC") at tests/parse-metric.c:189 #12 test_ipc () at tests/parse-metric.c:208 ..... ..... omitted many more lines This test case was added with commit 218ca91 ("perf tests: Add parse metric test for frontend metric"). When I compile with make DEBUG=y it works fine and I do not get a core dump. It turned out that the above listed function call chain worked on a struct pmu_event array which requires a trailing element with zeroes which was missing. The marco map_for_each_event() loops over that array tests for members metric_expr/metric_name/metric_group being non-NULL. Adding this element fixes the issue. Output after: [root@t35lp46 perf]# ./perf test 67 67: Parse and process metrics : Ok [root@t35lp46 perf]# Committer notes: As Ian remarks, this is not s390 specific: <quote Ian> This also shows up with address sanitizer on all architectures (perhaps change the patch title) and perhaps add a "Fixes: <commit>" tag. ================================================================= ==4718==ERROR: AddressSanitizer: global-buffer-overflow on address 0x55c93b4d59e8 at pc 0x55c93a1541e2 bp 0x7ffd24327c60 sp 0x7ffd24327c58 READ of size 8 at 0x55c93b4d59e8 thread T0 #0 0x55c93a1541e1 in find_metric tools/perf/util/metricgroup.c:764:2 #1 0x55c93a153e6c in __resolve_metric tools/perf/util/metricgroup.c:844:9 #2 0x55c93a152f18 in resolve_metric tools/perf/util/metricgroup.c:881:9 #3 0x55c93a1528db in metricgroup__add_metric tools/perf/util/metricgroup.c:943:9 #4 0x55c93a151996 in metricgroup__add_metric_list tools/perf/util/metricgroup.c:988:9 #5 0x55c93a1511b9 in parse_groups tools/perf/util/metricgroup.c:1040:8 #6 0x55c93a1513e1 in metricgroup__parse_groups_test tools/perf/util/metricgroup.c:1082:9 #7 0x55c93a0108ae in __compute_metric tools/perf/tests/parse-metric.c:159:8 #8 0x55c93a010744 in compute_metric tools/perf/tests/parse-metric.c:189:9 #9 0x55c93a00f5ee in test_ipc tools/perf/tests/parse-metric.c:208:2 #10 0x55c93a00f1e8 in test__parse_metric tools/perf/tests/parse-metric.c:345:2 #11 0x55c939fd7202 in run_test tools/perf/tests/builtin-test.c:410:9 #12 0x55c939fd6736 in test_and_print tools/perf/tests/builtin-test.c:440:9 #13 0x55c939fd58c3 in __cmd_test tools/perf/tests/builtin-test.c:661:4 #14 0x55c939fd4e02 in cmd_test tools/perf/tests/builtin-test.c:807:9 #15 0x55c939e4763d in run_builtin tools/perf/perf.c:313:11 #16 0x55c939e46475 in handle_internal_command tools/perf/perf.c:365:8 #17 0x55c939e4737e in run_argv tools/perf/perf.c:409:2 #18 0x55c939e45f7e in main tools/perf/perf.c:539:3 0x55c93b4d59e8 is located 0 bytes to the right of global variable 'pme_test' defined in 'tools/perf/tests/parse-metric.c:17:25' (0x55c93b4d54a0) of size 1352 SUMMARY: AddressSanitizer: global-buffer-overflow tools/perf/util/metricgroup.c:764:2 in find_metric Shadow bytes around the buggy address: 0x0ab9a7692ae0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692af0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692b10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692b20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 =>0x0ab9a7692b30: 00 00 00 00 00 00 00 00 00 00 00 00 00[f9]f9 f9 0x0ab9a7692b40: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 0x0ab9a7692b50: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 0x0ab9a7692b60: f9 f9 f9 f9 f9 f9 f9 f9 00 00 00 00 00 00 00 00 0x0ab9a7692b70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0x0ab9a7692b80: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb Shadow gap: cc </quote> I'm also adding the missing "Fixes" tag and setting just .name to NULL, as doing it that way is more compact (the compiler will zero out everything else) and the table iterators look for .name being NULL as the sentinel marking the end of the table. Fixes: 0a507af ("perf tests: Add parse metric test for ipc metric") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Acked-by: Ian Rogers <irogers@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Link: http://lore.kernel.org/lkml/20200825071211.16959-1-tmricht@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Yonghong Song says: ==================== Currently, the bpf hashmap iterator takes a bucket_lock, a spin_lock, before visiting each element in the bucket. This will cause a deadlock if a map update/delete operates on an element with the same bucket id of the visited map. To avoid the deadlock, let us just use rcu_read_lock instead of bucket_lock. This may result in visiting stale elements, missing some elements, or repeating some elements, if concurrent map delete/update happens for the same map. I think using rcu_read_lock is a reasonable compromise. For users caring stale/missing/repeating element issues, bpf map batch access syscall interface can be used. Note that another approach is during bpf_iter link stage, we check whether the iter program might be able to do update/delete to the visited map. If it is, reject the link_create. Verifier needs to record whether an update/delete operation happens for each map for this approach. I just feel this checking is too specialized, hence still prefer rcu_read_lock approach. Patch #1 has the kernel implementation and Patch #2 added a selftest which can trigger deadlock without Patch #1. ==================== Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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The dev_iommu_priv_set() must be called after probe_device(). This fixes a NULL pointer deference bug when booting a system with kernel cmdline "intel_iommu=on,igfx_off", where the dev_iommu_priv_set() is abused. The following stacktrace was produced: Command line: BOOT_IMAGE=/isolinux/bzImage console=tty1 intel_iommu=on,igfx_off ... DMAR: Host address width 39 DMAR: DRHD base: 0x000000fed90000 flags: 0x0 DMAR: dmar0: reg_base_addr fed90000 ver 1:0 cap 1c0000c40660462 ecap 19e2ff0505e DMAR: DRHD base: 0x000000fed91000 flags: 0x1 DMAR: dmar1: reg_base_addr fed91000 ver 1:0 cap d2008c40660462 ecap f050da DMAR: RMRR base: 0x0000009aa9f000 end: 0x0000009aabefff DMAR: RMRR base: 0x0000009d000000 end: 0x0000009f7fffff DMAR: No ATSR found BUG: kernel NULL pointer dereference, address: 0000000000000038 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP PTI CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.9.0-devel+ #2 Hardware name: LENOVO 20HGS0TW00/20HGS0TW00, BIOS N1WET46S (1.25s ) 03/30/2018 RIP: 0010:intel_iommu_init+0xed0/0x1136 Code: fe e9 61 02 00 00 bb f4 ff ff ff e9 57 02 00 00 48 63 d1 48 c1 e2 04 48 03 50 20 48 8b 12 48 85 d2 74 0b 48 8b 92 d0 02 00 00 48 89 7a 38 ff c1 e9 15 f5 ff ff 48 c7 c7 60 99 ac a7 49 c7 c7 a0 RSP: 0000:ffff96d180073dd0 EFLAGS: 00010282 RAX: ffff8c91037a7d20 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffffffffff RBP: ffff96d180073e90 R08: 0000000000000001 R09: ffff8c91039fe3c0 R10: 0000000000000226 R11: 0000000000000226 R12: 000000000000000b R13: ffff8c910367c650 R14: ffffffffa8426d60 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8c9107480000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000038 CR3: 00000004b100a001 CR4: 00000000003706e0 Call Trace: ? _raw_spin_unlock_irqrestore+0x1f/0x30 ? call_rcu+0x10e/0x320 ? trace_hardirqs_on+0x2c/0xd0 ? rdinit_setup+0x2c/0x2c ? e820__memblock_setup+0x8b/0x8b pci_iommu_init+0x16/0x3f do_one_initcall+0x46/0x1e4 kernel_init_freeable+0x169/0x1b2 ? rest_init+0x9f/0x9f kernel_init+0xa/0x101 ret_from_fork+0x22/0x30 Modules linked in: CR2: 0000000000000038 ---[ end trace 3653722a6f936f18 ]--- Fixes: 01b9d4e ("iommu/vt-d: Use dev_iommu_priv_get/set()") Reported-by: Torsten Hilbrich <torsten.hilbrich@secunet.com> Reported-by: Wendy Wang <wendy.wang@intel.com> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Torsten Hilbrich <torsten.hilbrich@secunet.com> Link: https://lore.kernel.org/linux-iommu/96717683-70be-7388-3d2f-61131070a96a@secunet.com/ Link: https://lore.kernel.org/r/20200903065132.16879-1-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
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Luo bin says: ==================== hinic: BugFixes The bugs fixed in this patchset have been present since the following commits: patch #1: Fixes: 00e57a6 ("net-next/hinic: Add Tx operation") patch #2: Fixes: 5e126e7 ("hinic: add firmware update support") ==================== Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Nikolay reported a lockdep splat in generic/476 that I could reproduce with btrfs/187. ====================================================== WARNING: possible circular locking dependency detected 5.9.0-rc2+ #1 Tainted: G W ------------------------------------------------------ kswapd0/100 is trying to acquire lock: ffff9e8ef38b6268 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x330 but task is already holding lock: ffffffffa9d74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (fs_reclaim){+.+.}-{0:0}: fs_reclaim_acquire+0x65/0x80 slab_pre_alloc_hook.constprop.0+0x20/0x200 kmem_cache_alloc_trace+0x3a/0x1a0 btrfs_alloc_device+0x43/0x210 add_missing_dev+0x20/0x90 read_one_chunk+0x301/0x430 btrfs_read_sys_array+0x17b/0x1b0 open_ctree+0xa62/0x1896 btrfs_mount_root.cold+0x12/0xea legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 vfs_kern_mount.part.0+0x71/0xb0 btrfs_mount+0x10d/0x379 legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 path_mount+0x434/0xc00 __x64_sys_mount+0xe3/0x120 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}: __mutex_lock+0x7e/0x7e0 btrfs_chunk_alloc+0x125/0x3a0 find_free_extent+0xdf6/0x1210 btrfs_reserve_extent+0xb3/0x1b0 btrfs_alloc_tree_block+0xb0/0x310 alloc_tree_block_no_bg_flush+0x4a/0x60 __btrfs_cow_block+0x11a/0x530 btrfs_cow_block+0x104/0x220 btrfs_search_slot+0x52e/0x9d0 btrfs_lookup_inode+0x2a/0x8f __btrfs_update_delayed_inode+0x80/0x240 btrfs_commit_inode_delayed_inode+0x119/0x120 btrfs_evict_inode+0x357/0x500 evict+0xcf/0x1f0 vfs_rmdir.part.0+0x149/0x160 do_rmdir+0x136/0x1a0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&delayed_node->mutex){+.+.}-{3:3}: __lock_acquire+0x1184/0x1fa0 lock_acquire+0xa4/0x3d0 __mutex_lock+0x7e/0x7e0 __btrfs_release_delayed_node.part.0+0x3f/0x330 btrfs_evict_inode+0x24c/0x500 evict+0xcf/0x1f0 dispose_list+0x48/0x70 prune_icache_sb+0x44/0x50 super_cache_scan+0x161/0x1e0 do_shrink_slab+0x178/0x3c0 shrink_slab+0x17c/0x290 shrink_node+0x2b2/0x6d0 balance_pgdat+0x30a/0x670 kswapd+0x213/0x4c0 kthread+0x138/0x160 ret_from_fork+0x1f/0x30 other info that might help us debug this: Chain exists of: &delayed_node->mutex --> &fs_info->chunk_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&fs_info->chunk_mutex); lock(fs_reclaim); lock(&delayed_node->mutex); *** DEADLOCK *** 3 locks held by kswapd0/100: #0: ffffffffa9d74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 #1: ffffffffa9d65c50 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x115/0x290 #2: ffff9e8e9da260e0 (&type->s_umount_key#48){++++}-{3:3}, at: super_cache_scan+0x38/0x1e0 stack backtrace: CPU: 1 PID: 100 Comm: kswapd0 Tainted: G W 5.9.0-rc2+ #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014 Call Trace: dump_stack+0x92/0xc8 check_noncircular+0x12d/0x150 __lock_acquire+0x1184/0x1fa0 lock_acquire+0xa4/0x3d0 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 __mutex_lock+0x7e/0x7e0 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 ? __btrfs_release_delayed_node.part.0+0x3f/0x330 ? lock_acquire+0xa4/0x3d0 ? btrfs_evict_inode+0x11e/0x500 ? find_held_lock+0x2b/0x80 __btrfs_release_delayed_node.part.0+0x3f/0x330 btrfs_evict_inode+0x24c/0x500 evict+0xcf/0x1f0 dispose_list+0x48/0x70 prune_icache_sb+0x44/0x50 super_cache_scan+0x161/0x1e0 do_shrink_slab+0x178/0x3c0 shrink_slab+0x17c/0x290 shrink_node+0x2b2/0x6d0 balance_pgdat+0x30a/0x670 kswapd+0x213/0x4c0 ? _raw_spin_unlock_irqrestore+0x46/0x60 ? add_wait_queue_exclusive+0x70/0x70 ? balance_pgdat+0x670/0x670 kthread+0x138/0x160 ? kthread_create_worker_on_cpu+0x40/0x40 ret_from_fork+0x1f/0x30 This is because we are holding the chunk_mutex when we call btrfs_alloc_device, which does a GFP_KERNEL allocation. We don't want to switch that to a GFP_NOFS lock because this is the only place where it matters. So instead use memalloc_nofs_save() around the allocation in order to avoid the lockdep splat. Reported-by: Nikolay Borisov <nborisov@suse.com> CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
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…arnings Since commit 845e0eb ("net: change addr_list_lock back to static key"), cascaded DSA setups (DSA switch port as DSA master for another DSA switch port) are emitting this lockdep warning: ============================================ WARNING: possible recursive locking detected 5.8.0-rc1-00133-g923e4b5032dd-dirty #208 Not tainted -------------------------------------------- dhcpcd/323 is trying to acquire lock: ffff000066dd4268 (&dsa_master_addr_list_lock_key/1){+...}-{2:2}, at: dev_mc_sync+0x44/0x90 but task is already holding lock: ffff00006608c268 (&dsa_master_addr_list_lock_key/1){+...}-{2:2}, at: dev_mc_sync+0x44/0x90 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&dsa_master_addr_list_lock_key/1); lock(&dsa_master_addr_list_lock_key/1); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by dhcpcd/323: #0: ffffdbd1381dda18 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x24/0x30 #1: ffff00006614b268 (_xmit_ETHER){+...}-{2:2}, at: dev_set_rx_mode+0x28/0x48 #2: ffff00006608c268 (&dsa_master_addr_list_lock_key/1){+...}-{2:2}, at: dev_mc_sync+0x44/0x90 stack backtrace: Call trace: dump_backtrace+0x0/0x1e0 show_stack+0x20/0x30 dump_stack+0xec/0x158 __lock_acquire+0xca0/0x2398 lock_acquire+0xe8/0x440 _raw_spin_lock_nested+0x64/0x90 dev_mc_sync+0x44/0x90 dsa_slave_set_rx_mode+0x34/0x50 __dev_set_rx_mode+0x60/0xa0 dev_mc_sync+0x84/0x90 dsa_slave_set_rx_mode+0x34/0x50 __dev_set_rx_mode+0x60/0xa0 dev_set_rx_mode+0x30/0x48 __dev_open+0x10c/0x180 __dev_change_flags+0x170/0x1c8 dev_change_flags+0x2c/0x70 devinet_ioctl+0x774/0x878 inet_ioctl+0x348/0x3b0 sock_do_ioctl+0x50/0x310 sock_ioctl+0x1f8/0x580 ksys_ioctl+0xb0/0xf0 __arm64_sys_ioctl+0x28/0x38 el0_svc_common.constprop.0+0x7c/0x180 do_el0_svc+0x2c/0x98 el0_sync_handler+0x9c/0x1b8 el0_sync+0x158/0x180 Since DSA never made use of the netdev API for describing links between upper devices and lower devices, the dev->lower_level value of a DSA switch interface would be 1, which would warn when it is a DSA master. We can use netdev_upper_dev_link() to describe the relationship between a DSA slave and a DSA master. To be precise, a DSA "slave" (switch port) is an "upper" to a DSA "master" (host port). The relationship is "many uppers to one lower", like in the case of VLAN. So, for that reason, we use the same function as VLAN uses. There might be a chance that somebody will try to take hold of this interface and use it immediately after register_netdev() and before netdev_upper_dev_link(). To avoid that, we do the registration and linkage while holding the RTNL, and we use the RTNL-locked cousin of register_netdev(), which is register_netdevice(). Since this warning was not there when lockdep was using dynamic keys for addr_list_lock, we are blaming the lockdep patch itself. The network stack _has_ been using static lockdep keys before, and it _is_ likely that stacked DSA setups have been triggering these lockdep warnings since forever, however I can't test very old kernels on this particular stacked DSA setup, to ensure I'm not in fact introducing regressions. Fixes: 845e0eb ("net: change addr_list_lock back to static key") Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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syzbot reported twice a lockdep issue in fib6_del() [1]
which I think is caused by net->ipv6.fib6_null_entry
having a NULL fib6_table pointer.
fib6_del() already checks for fib6_null_entry special
case, we only need to return earlier.
Bug seems to occur very rarely, I have thus chosen
a 'bug origin' that makes backports not too complex.
[1]
WARNING: suspicious RCU usage
5.9.0-rc4-syzkaller #0 Not tainted
-----------------------------
net/ipv6/ip6_fib.c:1996 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.5/8095:
#0: ffffffff8a7ea708 (rtnl_mutex){+.+.}-{3:3}, at: ppp_release+0x178/0x240 drivers/net/ppp/ppp_generic.c:401
#1: ffff88804c422dd8 (&net->ipv6.fib6_gc_lock){+.-.}-{2:2}, at: spin_trylock_bh include/linux/spinlock.h:414 [inline]
#1: ffff88804c422dd8 (&net->ipv6.fib6_gc_lock){+.-.}-{2:2}, at: fib6_run_gc+0x21b/0x2d0 net/ipv6/ip6_fib.c:2312
#2: ffffffff89bd6a40 (rcu_read_lock){....}-{1:2}, at: __fib6_clean_all+0x0/0x290 net/ipv6/ip6_fib.c:2613
#3: ffff8880a82e6430 (&tb->tb6_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:359 [inline]
#3: ffff8880a82e6430 (&tb->tb6_lock){+.-.}-{2:2}, at: __fib6_clean_all+0x107/0x290 net/ipv6/ip6_fib.c:2245
stack backtrace:
CPU: 1 PID: 8095 Comm: syz-executor.5 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x198/0x1fd lib/dump_stack.c:118
fib6_del+0x12b4/0x1630 net/ipv6/ip6_fib.c:1996
fib6_clean_node+0x39b/0x570 net/ipv6/ip6_fib.c:2180
fib6_walk_continue+0x4aa/0x8e0 net/ipv6/ip6_fib.c:2102
fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2150
fib6_clean_tree+0xdb/0x120 net/ipv6/ip6_fib.c:2230
__fib6_clean_all+0x120/0x290 net/ipv6/ip6_fib.c:2246
fib6_clean_all net/ipv6/ip6_fib.c:2257 [inline]
fib6_run_gc+0x113/0x2d0 net/ipv6/ip6_fib.c:2320
ndisc_netdev_event+0x217/0x350 net/ipv6/ndisc.c:1805
notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2033
call_netdevice_notifiers_extack net/core/dev.c:2045 [inline]
call_netdevice_notifiers net/core/dev.c:2059 [inline]
dev_close_many+0x30b/0x650 net/core/dev.c:1634
rollback_registered_many+0x3a8/0x1210 net/core/dev.c:9261
rollback_registered net/core/dev.c:9329 [inline]
unregister_netdevice_queue+0x2dd/0x570 net/core/dev.c:10410
unregister_netdevice include/linux/netdevice.h:2774 [inline]
ppp_release+0x216/0x240 drivers/net/ppp/ppp_generic.c:403
__fput+0x285/0x920 fs/file_table.c:281
task_work_run+0xdd/0x190 kernel/task_work.c:141
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop kernel/entry/common.c:163 [inline]
exit_to_user_mode_prepare+0x1e1/0x200 kernel/entry/common.c:190
syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:265
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 421842e ("net/ipv6: Add fib6_null_entry")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsahern@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Ido Schimmel says: ==================== net: Fix bridge enslavement failure Patch #1 fixes an issue in which an upper netdev cannot be enslaved to a bridge when it has multiple netdevs with different parent identifiers beneath it. Patch #2 adds a test case using two netdevsim instances. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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When compiling with DEBUG=1 on Fedora 32 I'm getting crash for 'perf test signal': Program received signal SIGSEGV, Segmentation fault. 0x0000000000c68548 in __test_function () (gdb) bt #0 0x0000000000c68548 in __test_function () #1 0x00000000004d62e9 in test_function () at tests/bp_signal.c:61 #2 0x00000000004d689a in test__bp_signal (test=0xa8e280 <generic_ ... #3 0x00000000004b7d49 in run_test (test=0xa8e280 <generic_tests+1 ... #4 0x00000000004b7e7f in test_and_print (t=0xa8e280 <generic_test ... #5 0x00000000004b8927 in __cmd_test (argc=1, argv=0x7fffffffdce0, ... ... It's caused by the symbol __test_function being in the ".bss" section: $ readelf -a ./perf | less [Nr] Name Type Address Offset Size EntSize Flags Link Info Align ... [28] .bss NOBITS 0000000000c356a0 008346a0 00000000000511f8 0000000000000000 WA 0 0 32 $ nm perf | grep __test_function 0000000000c68548 B __test_function I guess most of the time we're just lucky the inline asm ended up in the ".text" section, so making it specific explicit with push and pop section clauses. $ readelf -a ./perf | less [Nr] Name Type Address Offset Size EntSize Flags Link Info Align ... [13] .text PROGBITS 0000000000431240 00031240 0000000000306faa 0000000000000000 AX 0 0 16 $ nm perf | grep __test_function 00000000004d62c8 T __test_function Committer testing: $ readelf -wi ~/bin/perf | grep producer -m1 <c> DW_AT_producer : (indirect string, offset: 0x254a): GNU C99 10.2.1 20200723 (Red Hat 10.2.1-1) -mtune=generic -march=x86-64 -ggdb3 -std=gnu99 -fno-omit-frame-pointer -funwind-tables -fstack-protector-all ^^^^^ ^^^^^ ^^^^^ $ Before: $ perf test signal 20: Breakpoint overflow signal handler : FAILED! $ After: $ perf test signal 20: Breakpoint overflow signal handler : Ok $ Fixes: 8fd34e1 ("perf test: Improve bp_signal") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lore.kernel.org/lkml/20200911130005.1842138-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The aliases were never released causing the following leaks:
Indirect leak of 1224 byte(s) in 9 object(s) allocated from:
#0 0x7feefb830628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628)
#1 0x56332c8f1b62 in __perf_pmu__new_alias util/pmu.c:322
#2 0x56332c8f401f in pmu_add_cpu_aliases_map util/pmu.c:778
#3 0x56332c792ce9 in __test__pmu_event_aliases tests/pmu-events.c:295
#4 0x56332c792ce9 in test_aliases tests/pmu-events.c:367
#5 0x56332c76a09b in run_test tests/builtin-test.c:410
#6 0x56332c76a09b in test_and_print tests/builtin-test.c:440
#7 0x56332c76ce69 in __cmd_test tests/builtin-test.c:695
#8 0x56332c76ce69 in cmd_test tests/builtin-test.c:807
#9 0x56332c7d2214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#10 0x56332c6701a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#11 0x56332c6701a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#12 0x56332c6701a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#13 0x7feefb359cc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: 956a783 ("perf test: Test pmu-events aliases")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-11-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The evsel->unit borrows a pointer of pmu event or alias instead of
owns a string. But tool event (duration_time) passes a result of
strdup() caused a leak.
It was found by ASAN during metric test:
Direct leak of 210 byte(s) in 70 object(s) allocated from:
#0 0x7fe366fca0b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
#1 0x559fbbcc6ea3 in add_event_tool util/parse-events.c:414
#2 0x559fbbcc6ea3 in parse_events_add_tool util/parse-events.c:1414
#3 0x559fbbd8474d in parse_events_parse util/parse-events.y:439
#4 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096
#5 0x559fbbcc95da in __parse_events util/parse-events.c:2141
#6 0x559fbbc28555 in check_parse_id tests/pmu-events.c:406
#7 0x559fbbc28555 in check_parse_id tests/pmu-events.c:393
#8 0x559fbbc28555 in check_parse_cpu tests/pmu-events.c:415
#9 0x559fbbc28555 in test_parsing tests/pmu-events.c:498
#10 0x559fbbc0109b in run_test tests/builtin-test.c:410
#11 0x559fbbc0109b in test_and_print tests/builtin-test.c:440
#12 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695
#13 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807
#14 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#15 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#16 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#17 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#18 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: f0fbb11 ("perf stat: Implement duration_time as a proper event")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-6-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The test_generic_metric() missed to release entries in the pctx. Asan
reported following leak (and more):
Direct leak of 128 byte(s) in 1 object(s) allocated from:
#0 0x7f4c9396980e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e)
#1 0x55f7e748cc14 in hashmap_grow (/home/namhyung/project/linux/tools/perf/perf+0x90cc14)
#2 0x55f7e748d497 in hashmap__insert (/home/namhyung/project/linux/tools/perf/perf+0x90d497)
#3 0x55f7e7341667 in hashmap__set /home/namhyung/project/linux/tools/perf/util/hashmap.h:111
#4 0x55f7e7341667 in expr__add_ref util/expr.c:120
#5 0x55f7e7292436 in prepare_metric util/stat-shadow.c:783
#6 0x55f7e729556d in test_generic_metric util/stat-shadow.c:858
#7 0x55f7e712390b in compute_single tests/parse-metric.c:128
#8 0x55f7e712390b in __compute_metric tests/parse-metric.c:180
#9 0x55f7e712446d in compute_metric tests/parse-metric.c:196
#10 0x55f7e712446d in test_dcache_l2 tests/parse-metric.c:295
#11 0x55f7e712446d in test__parse_metric tests/parse-metric.c:355
#12 0x55f7e70be09b in run_test tests/builtin-test.c:410
#13 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
#14 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
#15 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
#16 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#17 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#18 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#19 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#20 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: 6d432c4 ("perf tools: Add test_generic_metric function")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-8-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The metricgroup__add_metric() can find multiple match for a metric group
and it's possible to fail. Also it can fail in the middle like in
resolve_metric() even for single metric.
In those cases, the intermediate list and ids will be leaked like:
Direct leak of 3 byte(s) in 1 object(s) allocated from:
#0 0x7f4c938f40b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5)
#1 0x55f7e71c1bef in __add_metric util/metricgroup.c:683
#2 0x55f7e71c31d0 in add_metric util/metricgroup.c:906
#3 0x55f7e71c3844 in metricgroup__add_metric util/metricgroup.c:940
#4 0x55f7e71c488d in metricgroup__add_metric_list util/metricgroup.c:993
#5 0x55f7e71c488d in parse_groups util/metricgroup.c:1045
#6 0x55f7e71c60a4 in metricgroup__parse_groups_test util/metricgroup.c:1087
#7 0x55f7e71235ae in __compute_metric tests/parse-metric.c:164
#8 0x55f7e7124650 in compute_metric tests/parse-metric.c:196
#9 0x55f7e7124650 in test_recursion_fail tests/parse-metric.c:318
#10 0x55f7e7124650 in test__parse_metric tests/parse-metric.c:356
#11 0x55f7e70be09b in run_test tests/builtin-test.c:410
#12 0x55f7e70be09b in test_and_print tests/builtin-test.c:440
#13 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661
#14 0x55f7e70c101a in cmd_test tests/builtin-test.c:807
#15 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#16 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#17 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#18 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#19 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: 83de0b7 ("perf metric: Collect referenced metrics in struct metric_ref_node")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-9-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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The following leaks were detected by ASAN:
Indirect leak of 360 byte(s) in 9 object(s) allocated from:
#0 0x7fecc305180e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e)
#1 0x560578f6dce5 in perf_pmu__new_format util/pmu.c:1333
#2 0x560578f752fc in perf_pmu_parse util/pmu.y:59
#3 0x560578f6a8b7 in perf_pmu__format_parse util/pmu.c:73
#4 0x560578e07045 in test__pmu tests/pmu.c:155
#5 0x560578de109b in run_test tests/builtin-test.c:410
#6 0x560578de109b in test_and_print tests/builtin-test.c:440
#7 0x560578de401a in __cmd_test tests/builtin-test.c:661
#8 0x560578de401a in cmd_test tests/builtin-test.c:807
#9 0x560578e49354 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
#10 0x560578ce71a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
#11 0x560578ce71a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
#12 0x560578ce71a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
#13 0x7fecc2b7acc9 in __libc_start_main ../csu/libc-start.c:308
Fixes: cff7f95 ("perf tests: Move pmu tests into separate object")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200915031819.386559-12-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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…kernel/git/kvmarm/kvmarm into kvm-master KVM/arm64 fixes for 5.9, take #2 - Fix handling of S1 Page Table Walk permission fault at S2 on instruction fetch - Cleanup kvm_vcpu_dabt_iswrite()
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syzbot reports a potential lock deadlock between the normal IO path and
->show_fdinfo():
======================================================
WARNING: possible circular locking dependency detected
5.9.0-rc6-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor.2/19710 is trying to acquire lock:
ffff888098ddc450 (sb_writers#4){.+.+}-{0:0}, at: io_write+0x6b5/0xb30 fs/io_uring.c:3296
but task is already holding lock:
ffff8880a11b8428 (&ctx->uring_lock){+.+.}-{3:3}, at: __do_sys_io_uring_enter+0xe9a/0x1bd0 fs/io_uring.c:8348
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&ctx->uring_lock){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:956 [inline]
__mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103
__io_uring_show_fdinfo fs/io_uring.c:8417 [inline]
io_uring_show_fdinfo+0x194/0xc70 fs/io_uring.c:8460
seq_show+0x4a8/0x700 fs/proc/fd.c:65
seq_read+0x432/0x1070 fs/seq_file.c:208
do_loop_readv_writev fs/read_write.c:734 [inline]
do_loop_readv_writev fs/read_write.c:721 [inline]
do_iter_read+0x48e/0x6e0 fs/read_write.c:955
vfs_readv+0xe5/0x150 fs/read_write.c:1073
kernel_readv fs/splice.c:355 [inline]
default_file_splice_read.constprop.0+0x4e6/0x9e0 fs/splice.c:412
do_splice_to+0x137/0x170 fs/splice.c:871
splice_direct_to_actor+0x307/0x980 fs/splice.c:950
do_splice_direct+0x1b3/0x280 fs/splice.c:1059
do_sendfile+0x55f/0xd40 fs/read_write.c:1540
__do_sys_sendfile64 fs/read_write.c:1601 [inline]
__se_sys_sendfile64 fs/read_write.c:1587 [inline]
__x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1587
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #1 (&p->lock){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:956 [inline]
__mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103
seq_read+0x61/0x1070 fs/seq_file.c:155
pde_read fs/proc/inode.c:306 [inline]
proc_reg_read+0x221/0x300 fs/proc/inode.c:318
do_loop_readv_writev fs/read_write.c:734 [inline]
do_loop_readv_writev fs/read_write.c:721 [inline]
do_iter_read+0x48e/0x6e0 fs/read_write.c:955
vfs_readv+0xe5/0x150 fs/read_write.c:1073
kernel_readv fs/splice.c:355 [inline]
default_file_splice_read.constprop.0+0x4e6/0x9e0 fs/splice.c:412
do_splice_to+0x137/0x170 fs/splice.c:871
splice_direct_to_actor+0x307/0x980 fs/splice.c:950
do_splice_direct+0x1b3/0x280 fs/splice.c:1059
do_sendfile+0x55f/0xd40 fs/read_write.c:1540
__do_sys_sendfile64 fs/read_write.c:1601 [inline]
__se_sys_sendfile64 fs/read_write.c:1587 [inline]
__x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1587
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #0 (sb_writers#4){.+.+}-{0:0}:
check_prev_add kernel/locking/lockdep.c:2496 [inline]
check_prevs_add kernel/locking/lockdep.c:2601 [inline]
validate_chain kernel/locking/lockdep.c:3218 [inline]
__lock_acquire+0x2a96/0x5780 kernel/locking/lockdep.c:4441
lock_acquire+0x1f3/0xaf0 kernel/locking/lockdep.c:5029
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write+0x228/0x450 fs/super.c:1672
io_write+0x6b5/0xb30 fs/io_uring.c:3296
io_issue_sqe+0x18f/0x5c50 fs/io_uring.c:5719
__io_queue_sqe+0x280/0x1160 fs/io_uring.c:6175
io_queue_sqe+0x692/0xfa0 fs/io_uring.c:6254
io_submit_sqe fs/io_uring.c:6324 [inline]
io_submit_sqes+0x1761/0x2400 fs/io_uring.c:6521
__do_sys_io_uring_enter+0xeac/0x1bd0 fs/io_uring.c:8349
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
other info that might help us debug this:
Chain exists of:
sb_writers#4 --> &p->lock --> &ctx->uring_lock
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ctx->uring_lock);
lock(&p->lock);
lock(&ctx->uring_lock);
lock(sb_writers#4);
*** DEADLOCK ***
1 lock held by syz-executor.2/19710:
#0: ffff8880a11b8428 (&ctx->uring_lock){+.+.}-{3:3}, at: __do_sys_io_uring_enter+0xe9a/0x1bd0 fs/io_uring.c:8348
stack backtrace:
CPU: 0 PID: 19710 Comm: syz-executor.2 Not tainted 5.9.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x198/0x1fd lib/dump_stack.c:118
check_noncircular+0x324/0x3e0 kernel/locking/lockdep.c:1827
check_prev_add kernel/locking/lockdep.c:2496 [inline]
check_prevs_add kernel/locking/lockdep.c:2601 [inline]
validate_chain kernel/locking/lockdep.c:3218 [inline]
__lock_acquire+0x2a96/0x5780 kernel/locking/lockdep.c:4441
lock_acquire+0x1f3/0xaf0 kernel/locking/lockdep.c:5029
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write+0x228/0x450 fs/super.c:1672
io_write+0x6b5/0xb30 fs/io_uring.c:3296
io_issue_sqe+0x18f/0x5c50 fs/io_uring.c:5719
__io_queue_sqe+0x280/0x1160 fs/io_uring.c:6175
io_queue_sqe+0x692/0xfa0 fs/io_uring.c:6254
io_submit_sqe fs/io_uring.c:6324 [inline]
io_submit_sqes+0x1761/0x2400 fs/io_uring.c:6521
__do_sys_io_uring_enter+0xeac/0x1bd0 fs/io_uring.c:8349
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e179
Code: 3d b2 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 0b b2 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1194e74c78 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa
RAX: ffffffffffffffda RBX: 00000000000082c0 RCX: 000000000045e179
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000004
RBP: 000000000118cf98 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffd1aa5756f R14: 00007f1194e759c0 R15: 000000000118cf4c
Fix this by just not diving into details if we fail to trylock the
io_uring mutex. We know the ctx isn't going away during this operation,
but we cannot safely iterate buffers/files/personalities if we don't
hold the io_uring mutex.
Reported-by: syzbot+2f8fa4e860edc3066aba@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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This patch is to add a new variable 'nested_level' into the net_device
structure.
This variable will be used as a parameter of spin_lock_nested() of
dev->addr_list_lock.
netif_addr_lock() can be called recursively so spin_lock_nested() is
used instead of spin_lock() and dev->lower_level is used as a parameter
of spin_lock_nested().
But, dev->lower_level value can be updated while it is being used.
So, lockdep would warn a possible deadlock scenario.
When a stacked interface is deleted, netif_{uc | mc}_sync() is
called recursively.
So, spin_lock_nested() is called recursively too.
At this moment, the dev->lower_level variable is used as a parameter of it.
dev->lower_level value is updated when interfaces are being unlinked/linked
immediately.
Thus, After unlinking, dev->lower_level shouldn't be a parameter of
spin_lock_nested().
A (macvlan)
|
B (vlan)
|
C (bridge)
|
D (macvlan)
|
E (vlan)
|
F (bridge)
A->lower_level : 6
B->lower_level : 5
C->lower_level : 4
D->lower_level : 3
E->lower_level : 2
F->lower_level : 1
When an interface 'A' is removed, it releases resources.
At this moment, netif_addr_lock() would be called.
Then, netdev_upper_dev_unlink() is called recursively.
Then dev->lower_level is updated.
There is no problem.
But, when the bridge module is removed, 'C' and 'F' interfaces
are removed at once.
If 'F' is removed first, a lower_level value is like below.
A->lower_level : 5
B->lower_level : 4
C->lower_level : 3
D->lower_level : 2
E->lower_level : 1
F->lower_level : 1
Then, 'C' is removed. at this moment, netif_addr_lock() is called
recursively.
The ordering is like this.
C(3)->D(2)->E(1)->F(1)
At this moment, the lower_level value of 'E' and 'F' are the same.
So, lockdep warns a possible deadlock scenario.
In order to avoid this problem, a new variable 'nested_level' is added.
This value is the same as dev->lower_level - 1.
But this value is updated in rtnl_unlock().
So, this variable can be used as a parameter of spin_lock_nested() safely
in the rtnl context.
Test commands:
ip link add br0 type bridge vlan_filtering 1
ip link add vlan1 link br0 type vlan id 10
ip link add macvlan2 link vlan1 type macvlan
ip link add br3 type bridge vlan_filtering 1
ip link set macvlan2 master br3
ip link add vlan4 link br3 type vlan id 10
ip link add macvlan5 link vlan4 type macvlan
ip link add br6 type bridge vlan_filtering 1
ip link set macvlan5 master br6
ip link add vlan7 link br6 type vlan id 10
ip link add macvlan8 link vlan7 type macvlan
ip link set br0 up
ip link set vlan1 up
ip link set macvlan2 up
ip link set br3 up
ip link set vlan4 up
ip link set macvlan5 up
ip link set br6 up
ip link set vlan7 up
ip link set macvlan8 up
modprobe -rv bridge
Splat looks like:
[ 36.057436][ T744] WARNING: possible recursive locking detected
[ 36.058848][ T744] 5.9.0-rc6+ #728 Not tainted
[ 36.059959][ T744] --------------------------------------------
[ 36.061391][ T744] ip/744 is trying to acquire lock:
[ 36.062590][ T744] ffff8c4767509280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: dev_set_rx_mode+0x19/0x30
[ 36.064922][ T744]
[ 36.064922][ T744] but task is already holding lock:
[ 36.066626][ T744] ffff8c4767769280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: dev_uc_add+0x1e/0x60
[ 36.068851][ T744]
[ 36.068851][ T744] other info that might help us debug this:
[ 36.070731][ T744] Possible unsafe locking scenario:
[ 36.070731][ T744]
[ 36.072497][ T744] CPU0
[ 36.073238][ T744] ----
[ 36.074007][ T744] lock(&vlan_netdev_addr_lock_key);
[ 36.075290][ T744] lock(&vlan_netdev_addr_lock_key);
[ 36.076590][ T744]
[ 36.076590][ T744] *** DEADLOCK ***
[ 36.076590][ T744]
[ 36.078515][ T744] May be due to missing lock nesting notation
[ 36.078515][ T744]
[ 36.080491][ T744] 3 locks held by ip/744:
[ 36.081471][ T744] #0: ffffffff98571df0 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x236/0x490
[ 36.083614][ T744] #1: ffff8c4767769280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: dev_uc_add+0x1e/0x60
[ 36.085942][ T744] #2: ffff8c476c8da280 (&bridge_netdev_addr_lock_key/4){+...}-{2:2}, at: dev_uc_sync+0x39/0x80
[ 36.088400][ T744]
[ 36.088400][ T744] stack backtrace:
[ 36.089772][ T744] CPU: 6 PID: 744 Comm: ip Not tainted 5.9.0-rc6+ #728
[ 36.091364][ T744] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 36.093630][ T744] Call Trace:
[ 36.094416][ T744] dump_stack+0x77/0x9b
[ 36.095385][ T744] __lock_acquire+0xbc3/0x1f40
[ 36.096522][ T744] lock_acquire+0xb4/0x3b0
[ 36.097540][ T744] ? dev_set_rx_mode+0x19/0x30
[ 36.098657][ T744] ? rtmsg_ifinfo+0x1f/0x30
[ 36.099711][ T744] ? __dev_notify_flags+0xa5/0xf0
[ 36.100874][ T744] ? rtnl_is_locked+0x11/0x20
[ 36.101967][ T744] ? __dev_set_promiscuity+0x7b/0x1a0
[ 36.103230][ T744] _raw_spin_lock_bh+0x38/0x70
[ 36.104348][ T744] ? dev_set_rx_mode+0x19/0x30
[ 36.105461][ T744] dev_set_rx_mode+0x19/0x30
[ 36.106532][ T744] dev_set_promiscuity+0x36/0x50
[ 36.107692][ T744] __dev_set_promiscuity+0x123/0x1a0
[ 36.108929][ T744] dev_set_promiscuity+0x1e/0x50
[ 36.110093][ T744] br_port_set_promisc+0x1f/0x40 [bridge]
[ 36.111415][ T744] br_manage_promisc+0x8b/0xe0 [bridge]
[ 36.112728][ T744] __dev_set_promiscuity+0x123/0x1a0
[ 36.113967][ T744] ? __hw_addr_sync_one+0x23/0x50
[ 36.115135][ T744] __dev_set_rx_mode+0x68/0x90
[ 36.116249][ T744] dev_uc_sync+0x70/0x80
[ 36.117244][ T744] dev_uc_add+0x50/0x60
[ 36.118223][ T744] macvlan_open+0x18e/0x1f0 [macvlan]
[ 36.119470][ T744] __dev_open+0xd6/0x170
[ 36.120470][ T744] __dev_change_flags+0x181/0x1d0
[ 36.121644][ T744] dev_change_flags+0x23/0x60
[ 36.122741][ T744] do_setlink+0x30a/0x11e0
[ 36.123778][ T744] ? __lock_acquire+0x92c/0x1f40
[ 36.124929][ T744] ? __nla_validate_parse.part.6+0x45/0x8e0
[ 36.126309][ T744] ? __lock_acquire+0x92c/0x1f40
[ 36.127457][ T744] __rtnl_newlink+0x546/0x8e0
[ 36.128560][ T744] ? lock_acquire+0xb4/0x3b0
[ 36.129623][ T744] ? deactivate_slab.isra.85+0x6a1/0x850
[ 36.130946][ T744] ? __lock_acquire+0x92c/0x1f40
[ 36.132102][ T744] ? lock_acquire+0xb4/0x3b0
[ 36.133176][ T744] ? is_bpf_text_address+0x5/0xe0
[ 36.134364][ T744] ? rtnl_newlink+0x2e/0x70
[ 36.135445][ T744] ? rcu_read_lock_sched_held+0x32/0x60
[ 36.136771][ T744] ? kmem_cache_alloc_trace+0x2d8/0x380
[ 36.138070][ T744] ? rtnl_newlink+0x2e/0x70
[ 36.139164][ T744] rtnl_newlink+0x47/0x70
[ ... ]
Fixes: 845e0eb ("net: change addr_list_lock back to static key")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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When closing and freeing the source device we could end up doing our final blkdev_put() on the bdev, which will grab the bd_mutex. As such we want to be holding as few locks as possible, so move this call outside of the dev_replace->lock_finishing_cancel_unmount lock. Since we're modifying the fs_devices we need to make sure we're holding the uuid_mutex here, so take that as well. There's a report from syzbot probably hitting one of the cases where the bd_mutex and device_list_mutex are taken in the wrong order, however it's not with device replace, like this patch fixes. As there's no reproducer available so far, we can't verify the fix. https://lore.kernel.org/lkml/000000000000fc04d105afcf86d7@google.com/ dashboard link: https://syzkaller.appspot.com/bug?extid=84a0634dc5d21d488419 WARNING: possible circular locking dependency detected 5.9.0-rc5-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/6878 is trying to acquire lock: ffff88804c17d780 (&bdev->bd_mutex){+.+.}-{3:3}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1804 but task is already holding lock: ffff8880908cfce0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: close_fs_devices.part.0+0x2e/0x800 fs/btrfs/volumes.c:1159 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103 btrfs_finish_chunk_alloc+0x281/0xf90 fs/btrfs/volumes.c:5255 btrfs_create_pending_block_groups+0x2f3/0x700 fs/btrfs/block-group.c:2109 __btrfs_end_transaction+0xf5/0x690 fs/btrfs/transaction.c:916 find_free_extent_update_loop fs/btrfs/extent-tree.c:3807 [inline] find_free_extent+0x23b7/0x2e60 fs/btrfs/extent-tree.c:4127 btrfs_reserve_extent+0x166/0x460 fs/btrfs/extent-tree.c:4206 cow_file_range+0x3de/0x9b0 fs/btrfs/inode.c:1063 btrfs_run_delalloc_range+0x2cf/0x1410 fs/btrfs/inode.c:1838 writepage_delalloc+0x150/0x460 fs/btrfs/extent_io.c:3439 __extent_writepage+0x441/0xd00 fs/btrfs/extent_io.c:3653 extent_write_cache_pages.constprop.0+0x69d/0x1040 fs/btrfs/extent_io.c:4249 extent_writepages+0xcd/0x2b0 fs/btrfs/extent_io.c:4370 do_writepages+0xec/0x290 mm/page-writeback.c:2352 __writeback_single_inode+0x125/0x1400 fs/fs-writeback.c:1461 writeback_sb_inodes+0x53d/0xf40 fs/fs-writeback.c:1721 wb_writeback+0x2ad/0xd40 fs/fs-writeback.c:1894 wb_do_writeback fs/fs-writeback.c:2039 [inline] wb_workfn+0x2dc/0x13e0 fs/fs-writeback.c:2080 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 -> #3 (sb_internal#2){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write+0x234/0x470 fs/super.c:1672 sb_start_intwrite include/linux/fs.h:1690 [inline] start_transaction+0xbe7/0x1170 fs/btrfs/transaction.c:624 find_free_extent_update_loop fs/btrfs/extent-tree.c:3789 [inline] find_free_extent+0x25e1/0x2e60 fs/btrfs/extent-tree.c:4127 btrfs_reserve_extent+0x166/0x460 fs/btrfs/extent-tree.c:4206 cow_file_range+0x3de/0x9b0 fs/btrfs/inode.c:1063 btrfs_run_delalloc_range+0x2cf/0x1410 fs/btrfs/inode.c:1838 writepage_delalloc+0x150/0x460 fs/btrfs/extent_io.c:3439 __extent_writepage+0x441/0xd00 fs/btrfs/extent_io.c:3653 extent_write_cache_pages.constprop.0+0x69d/0x1040 fs/btrfs/extent_io.c:4249 extent_writepages+0xcd/0x2b0 fs/btrfs/extent_io.c:4370 do_writepages+0xec/0x290 mm/page-writeback.c:2352 __writeback_single_inode+0x125/0x1400 fs/fs-writeback.c:1461 writeback_sb_inodes+0x53d/0xf40 fs/fs-writeback.c:1721 wb_writeback+0x2ad/0xd40 fs/fs-writeback.c:1894 wb_do_writeback fs/fs-writeback.c:2039 [inline] wb_workfn+0x2dc/0x13e0 fs/fs-writeback.c:2080 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 -> #2 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}: __flush_work+0x60e/0xac0 kernel/workqueue.c:3041 wb_shutdown+0x180/0x220 mm/backing-dev.c:355 bdi_unregister+0x174/0x590 mm/backing-dev.c:872 del_gendisk+0x820/0xa10 block/genhd.c:933 loop_remove drivers/block/loop.c:2192 [inline] loop_control_ioctl drivers/block/loop.c:2291 [inline] loop_control_ioctl+0x3b1/0x480 drivers/block/loop.c:2257 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (loop_ctl_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103 lo_open+0x19/0xd0 drivers/block/loop.c:1893 __blkdev_get+0x759/0x1aa0 fs/block_dev.c:1507 blkdev_get fs/block_dev.c:1639 [inline] blkdev_open+0x227/0x300 fs/block_dev.c:1753 do_dentry_open+0x4b9/0x11b0 fs/open.c:817 do_open fs/namei.c:3251 [inline] path_openat+0x1b9a/0x2730 fs/namei.c:3368 do_filp_open+0x17e/0x3c0 fs/namei.c:3395 do_sys_openat2+0x16d/0x420 fs/open.c:1168 do_sys_open fs/open.c:1184 [inline] __do_sys_open fs/open.c:1192 [inline] __se_sys_open fs/open.c:1188 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1188 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&bdev->bd_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:2496 [inline] check_prevs_add kernel/locking/lockdep.c:2601 [inline] validate_chain kernel/locking/lockdep.c:3218 [inline] __lock_acquire+0x2a96/0x5780 kernel/locking/lockdep.c:4426 lock_acquire+0x1f3/0xae0 kernel/locking/lockdep.c:5006 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103 blkdev_put+0x30/0x520 fs/block_dev.c:1804 btrfs_close_bdev fs/btrfs/volumes.c:1117 [inline] btrfs_close_bdev fs/btrfs/volumes.c:1107 [inline] btrfs_close_one_device fs/btrfs/volumes.c:1133 [inline] close_fs_devices.part.0+0x1a4/0x800 fs/btrfs/volumes.c:1161 close_fs_devices fs/btrfs/volumes.c:1193 [inline] btrfs_close_devices+0x95/0x1f0 fs/btrfs/volumes.c:1179 close_ctree+0x688/0x6cb fs/btrfs/disk-io.c:4149 generic_shutdown_super+0x144/0x370 fs/super.c:464 kill_anon_super+0x36/0x60 fs/super.c:1108 btrfs_kill_super+0x38/0x50 fs/btrfs/super.c:2265 deactivate_locked_super+0x94/0x160 fs/super.c:335 deactivate_super+0xad/0xd0 fs/super.c:366 cleanup_mnt+0x3a3/0x530 fs/namespace.c:1118 task_work_run+0xdd/0x190 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:163 [inline] exit_to_user_mode_prepare+0x1e1/0x200 kernel/entry/common.c:190 syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:265 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Chain exists of: &bdev->bd_mutex --> sb_internal#2 --> &fs_devs->device_list_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_devs->device_list_mutex); lock(sb_internal#2); lock(&fs_devs->device_list_mutex); lock(&bdev->bd_mutex); *** DEADLOCK *** 3 locks held by syz-executor.0/6878: #0: ffff88809070c0e0 (&type->s_umount_key#70){++++}-{3:3}, at: deactivate_super+0xa5/0xd0 fs/super.c:365 #1: ffffffff8a5b37a8 (uuid_mutex){+.+.}-{3:3}, at: btrfs_close_devices+0x23/0x1f0 fs/btrfs/volumes.c:1178 #2: ffff8880908cfce0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: close_fs_devices.part.0+0x2e/0x800 fs/btrfs/volumes.c:1159 stack backtrace: CPU: 0 PID: 6878 Comm: syz-executor.0 Not tainted 5.9.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x198/0x1fd lib/dump_stack.c:118 check_noncircular+0x324/0x3e0 kernel/locking/lockdep.c:1827 check_prev_add kernel/locking/lockdep.c:2496 [inline] check_prevs_add kernel/locking/lockdep.c:2601 [inline] validate_chain kernel/locking/lockdep.c:3218 [inline] __lock_acquire+0x2a96/0x5780 kernel/locking/lockdep.c:4426 lock_acquire+0x1f3/0xae0 kernel/locking/lockdep.c:5006 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10e0 kernel/locking/mutex.c:1103 blkdev_put+0x30/0x520 fs/block_dev.c:1804 btrfs_close_bdev fs/btrfs/volumes.c:1117 [inline] btrfs_close_bdev fs/btrfs/volumes.c:1107 [inline] btrfs_close_one_device fs/btrfs/volumes.c:1133 [inline] close_fs_devices.part.0+0x1a4/0x800 fs/btrfs/volumes.c:1161 close_fs_devices fs/btrfs/volumes.c:1193 [inline] btrfs_close_devices+0x95/0x1f0 fs/btrfs/volumes.c:1179 close_ctree+0x688/0x6cb fs/btrfs/disk-io.c:4149 generic_shutdown_super+0x144/0x370 fs/super.c:464 kill_anon_super+0x36/0x60 fs/super.c:1108 btrfs_kill_super+0x38/0x50 fs/btrfs/super.c:2265 deactivate_locked_super+0x94/0x160 fs/super.c:335 deactivate_super+0xad/0xd0 fs/super.c:366 cleanup_mnt+0x3a3/0x530 fs/namespace.c:1118 task_work_run+0xdd/0x190 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:163 [inline] exit_to_user_mode_prepare+0x1e1/0x200 kernel/entry/common.c:190 syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:265 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x460027 RSP: 002b:00007fff59216328 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000076035 RCX: 0000000000460027 RDX: 0000000000403188 RSI: 0000000000000002 RDI: 00007fff592163d0 RBP: 0000000000000333 R08: 0000000000000000 R09: 000000000000000b R10: 0000000000000005 R11: 0000000000000246 R12: 00007fff59217460 R13: 0000000002df2a60 R14: 0000000000000000 R15: 00007fff59217460 Signed-off-by: Josef Bacik <josef@toxicpanda.com> [ add syzbot reference ] Signed-off-by: David Sterba <dsterba@suse.com>
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Ido Schimmel says: ==================== mlxsw: Couple of fixes Patch #1 fixes firmware flashing when CONFIG_MLXSW_CORE=y and CONFIG_MLXFW=m. Patch #2 prevents EMAD transactions from needlessly failing when the system is under heavy load by using exponential backoff. Please consider patch #2 for stable. ==================== Link: https://lore.kernel.org/r/20201117173352.288491-1-idosch@idosch.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Dec 16, 2020
When running test case btrfs/017 from fstests, lockdep reported the following splat: [ 1297.067385] ====================================================== [ 1297.067708] WARNING: possible circular locking dependency detected [ 1297.068022] 5.10.0-rc4-btrfs-next-73 #1 Not tainted [ 1297.068322] ------------------------------------------------------ [ 1297.068629] btrfs/189080 is trying to acquire lock: [ 1297.068929] ffff9f2725731690 (sb_internal#2){.+.+}-{0:0}, at: btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.069274] but task is already holding lock: [ 1297.069868] ffff9f2702b61a08 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_quota_enable+0x3b/0xa70 [btrfs] [ 1297.070219] which lock already depends on the new lock. [ 1297.071131] the existing dependency chain (in reverse order) is: [ 1297.071721] -> #1 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}: [ 1297.072375] lock_acquire+0xd8/0x490 [ 1297.072710] __mutex_lock+0xa3/0xb30 [ 1297.073061] btrfs_qgroup_inherit+0x59/0x6a0 [btrfs] [ 1297.073421] create_subvol+0x194/0x990 [btrfs] [ 1297.073780] btrfs_mksubvol+0x3fb/0x4a0 [btrfs] [ 1297.074133] __btrfs_ioctl_snap_create+0x119/0x1a0 [btrfs] [ 1297.074498] btrfs_ioctl_snap_create+0x58/0x80 [btrfs] [ 1297.074872] btrfs_ioctl+0x1a90/0x36f0 [btrfs] [ 1297.075245] __x64_sys_ioctl+0x83/0xb0 [ 1297.075617] do_syscall_64+0x33/0x80 [ 1297.075993] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1297.076380] -> #0 (sb_internal#2){.+.+}-{0:0}: [ 1297.077166] check_prev_add+0x91/0xc60 [ 1297.077572] __lock_acquire+0x1740/0x3110 [ 1297.077984] lock_acquire+0xd8/0x490 [ 1297.078411] start_transaction+0x3c5/0x760 [btrfs] [ 1297.078853] btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.079323] btrfs_ioctl+0x2c60/0x36f0 [btrfs] [ 1297.079789] __x64_sys_ioctl+0x83/0xb0 [ 1297.080232] do_syscall_64+0x33/0x80 [ 1297.080680] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1297.081139] other info that might help us debug this: [ 1297.082536] Possible unsafe locking scenario: [ 1297.083510] CPU0 CPU1 [ 1297.084005] ---- ---- [ 1297.084500] lock(&fs_info->qgroup_ioctl_lock); [ 1297.084994] lock(sb_internal#2); [ 1297.085485] lock(&fs_info->qgroup_ioctl_lock); [ 1297.085974] lock(sb_internal#2); [ 1297.086454] *** DEADLOCK *** [ 1297.087880] 3 locks held by btrfs/189080: [ 1297.088324] #0: ffff9f2725731470 (sb_writers#14){.+.+}-{0:0}, at: btrfs_ioctl+0xa73/0x36f0 [btrfs] [ 1297.088799] #1: ffff9f2702b60cc0 (&fs_info->subvol_sem){++++}-{3:3}, at: btrfs_ioctl+0x1f4d/0x36f0 [btrfs] [ 1297.089284] #2: ffff9f2702b61a08 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_quota_enable+0x3b/0xa70 [btrfs] [ 1297.089771] stack backtrace: [ 1297.090662] CPU: 5 PID: 189080 Comm: btrfs Not tainted 5.10.0-rc4-btrfs-next-73 #1 [ 1297.091132] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 1297.092123] Call Trace: [ 1297.092629] dump_stack+0x8d/0xb5 [ 1297.093115] check_noncircular+0xff/0x110 [ 1297.093596] check_prev_add+0x91/0xc60 [ 1297.094076] ? kvm_clock_read+0x14/0x30 [ 1297.094553] ? kvm_sched_clock_read+0x5/0x10 [ 1297.095029] __lock_acquire+0x1740/0x3110 [ 1297.095510] lock_acquire+0xd8/0x490 [ 1297.095993] ? btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.096476] start_transaction+0x3c5/0x760 [btrfs] [ 1297.096962] ? btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.097451] btrfs_quota_enable+0xaf/0xa70 [btrfs] [ 1297.097941] ? btrfs_ioctl+0x1f4d/0x36f0 [btrfs] [ 1297.098429] btrfs_ioctl+0x2c60/0x36f0 [btrfs] [ 1297.098904] ? do_user_addr_fault+0x20c/0x430 [ 1297.099382] ? kvm_clock_read+0x14/0x30 [ 1297.099854] ? kvm_sched_clock_read+0x5/0x10 [ 1297.100328] ? sched_clock+0x5/0x10 [ 1297.100801] ? sched_clock_cpu+0x12/0x180 [ 1297.101272] ? __x64_sys_ioctl+0x83/0xb0 [ 1297.101739] __x64_sys_ioctl+0x83/0xb0 [ 1297.102207] do_syscall_64+0x33/0x80 [ 1297.102673] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 1297.103148] RIP: 0033:0x7f773ff65d87 This is because during the quota enable ioctl we lock first the mutex qgroup_ioctl_lock and then start a transaction, and starting a transaction acquires a fs freeze semaphore (at the VFS level). However, every other code path, except for the quota disable ioctl path, we do the opposite: we start a transaction and then lock the mutex. So fix this by making the quota enable and disable paths to start the transaction without having the mutex locked, and then, after starting the transaction, lock the mutex and check if some other task already enabled or disabled the quotas, bailing with success if that was the case. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
john-cabaj
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Jun 17, 2024
This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4 ("rust: upgrade to Rust 1.68.2"). No unstable features that we use were stabilized in Rust 1.76.0. The only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list. Please see [3] for details. `rustc` (and others) now warns when it cannot connect to the Make jobserver, thus mark those invocations as recursive as needed. Please see the previous commit for details. Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore for DWARFv4 [4][5]. For instance, in the uncompressed debug info case, this debug information took: samples/rust/rust_minimal.o ~64 KiB (~18% of total object size) rust/kernel.o ~92 KiB (~15%) rust/core.o ~114 KiB ( ~5%) In the compressed debug info (zlib) case: samples/rust/rust_minimal.o ~11 KiB (~6%) rust/kernel.o ~17 KiB (~5%) rust/core.o ~21 KiB (~1.5%) In addition, the `rustc_codegen_gcc` backend now does not emit the `.eh_frame` section when compiling under `-Cpanic=abort` [6], thus removing the need for the patch in the CI to compile the kernel [7]. Moreover, it also now emits the `.comment` section too [6]. The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: Rust-for-Linux#2 [3] Link: rust-lang/compiler-team#688 [4] Link: rust-lang/rust#117962 [5] Link: rust-lang/rust#118068 [6] Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7] Tested-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20240217002638.57373-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org> (cherry picked from commit 6092708 https://github.com/AsahiLinux/linux) Signed-off-by: John Cabaj <john.cabaj@canonical.com>
fbq
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Jun 18, 2024
====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc2-ktest-00018-gebd1d148b278 #144 Not tainted ------------------------------------------------------ fio/1345 is trying to acquire lock: ffff88813e200ab8 (&c->snapshot_create_lock){++++}-{3:3}, at: bch2_truncate+0x76/0xf0 but task is already holding lock: ffff888105a1fa38 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: do_truncate+0x7b/0xc0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}: down_write+0x3d/0xd0 bch2_write_iter+0x1c0/0x10f0 vfs_write+0x24a/0x560 __x64_sys_pwrite64+0x77/0xb0 x64_sys_call+0x17e5/0x1ab0 do_syscall_64+0x68/0x130 entry_SYSCALL_64_after_hwframe+0x4b/0x53 -> #1 (sb_writers#10){.+.+}-{0:0}: mnt_want_write+0x4a/0x1d0 filename_create+0x69/0x1a0 user_path_create+0x38/0x50 bch2_fs_file_ioctl+0x315/0xbf0 __x64_sys_ioctl+0x297/0xaf0 x64_sys_call+0x10cb/0x1ab0 do_syscall_64+0x68/0x130 entry_SYSCALL_64_after_hwframe+0x4b/0x53 -> #0 (&c->snapshot_create_lock){++++}-{3:3}: __lock_acquire+0x1445/0x25b0 lock_acquire+0xbd/0x2b0 down_read+0x40/0x180 bch2_truncate+0x76/0xf0 bchfs_truncate+0x240/0x3f0 bch2_setattr+0x7b/0xb0 notify_change+0x322/0x4b0 do_truncate+0x8b/0xc0 do_ftruncate+0x110/0x270 __x64_sys_ftruncate+0x43/0x80 x64_sys_call+0x1373/0x1ab0 do_syscall_64+0x68/0x130 entry_SYSCALL_64_after_hwframe+0x4b/0x53 other info that might help us debug this: Chain exists of: &c->snapshot_create_lock --> sb_writers#10 --> &sb->s_type->i_mutex_key#13 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&sb->s_type->i_mutex_key#13); lock(sb_writers#10); lock(&sb->s_type->i_mutex_key#13); rlock(&c->snapshot_create_lock); *** DEADLOCK *** Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
fbq
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Jun 18, 2024
…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>
fbq
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Jun 18, 2024
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>
metaspace
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Jun 25, 2024
Synchronize the dev->driver usage in really_probe() and dev_uevent(). These can run in different threads, what can result in the following race condition for dev->driver uninitialization: Thread #1: ========== really_probe() { ... probe_failed: ... device_unbind_cleanup(dev) { ... dev->driver = NULL; // <= Failed probe sets dev->driver to NULL ... } ... } Thread Rust-for-Linux#2: ========== dev_uevent() { ... if (dev->driver) // If dev->driver is NULLed from really_probe() from here on, // after above check, the system crashes add_uevent_var(env, "DRIVER=%s", dev->driver->name); ... } really_probe() holds the lock, already. So nothing needs to be done there. dev_uevent() is called with lock held, often, too. But not always. What implies that we can't add any locking in dev_uevent() itself. So fix this race by adding the lock to the non-protected path. This is the path where above race is observed: dev_uevent+0x235/0x380 uevent_show+0x10c/0x1f0 <= Add lock here dev_attr_show+0x3a/0xa0 sysfs_kf_seq_show+0x17c/0x250 kernfs_seq_show+0x7c/0x90 seq_read_iter+0x2d7/0x940 kernfs_fop_read_iter+0xc6/0x310 vfs_read+0x5bc/0x6b0 ksys_read+0xeb/0x1b0 __x64_sys_read+0x42/0x50 x64_sys_call+0x27ad/0x2d30 do_syscall_64+0xcd/0x1d0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Similar cases are reported by syzkaller in https://syzkaller.appspot.com/bug?extid=ffa8143439596313a85a But these are regarding the *initialization* of dev->driver dev->driver = drv; As this switches dev->driver to non-NULL these reports can be considered to be false-positives (which should be "fixed" by this commit, as well, though). The same issue was reported and tried to be fixed back in 2015 in https://lore.kernel.org/lkml/1421259054-2574-1-git-send-email-a.sangwan@samsung.com/ already. Fixes: 239378f ("Driver core: add uevent vars for devices of a class") Cc: stable <stable@kernel.org> Cc: syzbot+ffa8143439596313a85a@syzkaller.appspotmail.com Cc: Ashish Sangwan <a.sangwan@samsung.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com> Link: https://lore.kernel.org/r/20240513050634.3964461-1-dirk.behme@de.bosch.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
metaspace
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Jun 25, 2024
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 Rust-for-Linux#2: 98% system, 0% softirq, 3% hardirq, 0% idle Rust-for-Linux#3: 98% system, 0% softirq, 3% hardirq, 0% idle Rust-for-Linux#4: 98% system, 0% softirq, 3% hardirq, 0% idle Rust-for-Linux#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>
metaspace
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Jun 25, 2024
Luis has been reporting an assert failure when freeing an inode cluster during inode inactivation for a while. The assert looks like: XFS: Assertion failed: bp->b_flags & XBF_DONE, file: fs/xfs/xfs_trans_buf.c, line: 241 ------------[ cut here ]------------ kernel BUG at fs/xfs/xfs_message.c:102! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 4 PID: 73 Comm: kworker/4:1 Not tainted 6.10.0-rc1 Rust-for-Linux#4 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: xfs-inodegc/loop5 xfs_inodegc_worker [xfs] RIP: 0010:assfail (fs/xfs/xfs_message.c:102) xfs RSP: 0018:ffff88810188f7f0 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff88816e748250 RCX: 1ffffffff844b0e7 RDX: 0000000000000004 RSI: ffff88810188f558 RDI: ffffffffc2431fa0 RBP: 1ffff11020311f01 R08: 0000000042431f9f R09: ffffed1020311e9b R10: ffff88810188f4df R11: ffffffffac725d70 R12: ffff88817a3f4000 R13: ffff88812182f000 R14: ffff88810188f998 R15: ffffffffc2423f80 FS: 0000000000000000(0000) GS:ffff8881c8400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055fe9d0f109c CR3: 000000014426c002 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> xfs_trans_read_buf_map (fs/xfs/xfs_trans_buf.c:241 (discriminator 1)) xfs xfs_imap_to_bp (fs/xfs/xfs_trans.h:210 fs/xfs/libxfs/xfs_inode_buf.c:138) xfs xfs_inode_item_precommit (fs/xfs/xfs_inode_item.c:145) xfs xfs_trans_run_precommits (fs/xfs/xfs_trans.c:931) xfs __xfs_trans_commit (fs/xfs/xfs_trans.c:966) xfs xfs_inactive_ifree (fs/xfs/xfs_inode.c:1811) xfs xfs_inactive (fs/xfs/xfs_inode.c:2013) xfs xfs_inodegc_worker (fs/xfs/xfs_icache.c:1841 fs/xfs/xfs_icache.c:1886) xfs process_one_work (kernel/workqueue.c:3231) worker_thread (kernel/workqueue.c:3306 (discriminator 2) kernel/workqueue.c:3393 (discriminator 2)) kthread (kernel/kthread.c:389) ret_from_fork (arch/x86/kernel/process.c:147) ret_from_fork_asm (arch/x86/entry/entry_64.S:257) </TASK> And occurs when the the inode precommit handlers is attempt to look up the inode cluster buffer to attach the inode for writeback. The trail of logic that I can reconstruct is as follows. 1. the inode is clean when inodegc runs, so it is not attached to a cluster buffer when precommit runs. 2. #1 implies the inode cluster buffer may be clean and not pinned by dirty inodes when inodegc runs. 3. Rust-for-Linux#2 implies that the inode cluster buffer can be reclaimed by memory pressure at any time. 4. The assert failure implies that the cluster buffer was attached to the transaction, but not marked done. It had been accessed earlier in the transaction, but not marked done. 5. Rust-for-Linux#4 implies the cluster buffer has been invalidated (i.e. marked stale). 6. Rust-for-Linux#5 implies that the inode cluster buffer was instantiated uninitialised in the transaction in xfs_ifree_cluster(), which only instantiates the buffers to invalidate them and never marks them as done. Given factors 1-3, this issue is highly dependent on timing and environmental factors. Hence the issue can be very difficult to reproduce in some situations, but highly reliable in others. Luis has an environment where it can be reproduced easily by g/531 but, OTOH, I've reproduced it only once in ~2000 cycles of g/531. I think the fix is to have xfs_ifree_cluster() set the XBF_DONE flag on the cluster buffers, even though they may not be initialised. The reasons why I think this is safe are: 1. A buffer cache lookup hit on a XBF_STALE buffer will clear the XBF_DONE flag. Hence all future users of the buffer know they have to re-initialise the contents before use and mark it done themselves. 2. xfs_trans_binval() sets the XFS_BLI_STALE flag, which means the buffer remains locked until the journal commit completes and the buffer is unpinned. Hence once marked XBF_STALE/XFS_BLI_STALE by xfs_ifree_cluster(), the only context that can access the freed buffer is the currently running transaction. 3. Rust-for-Linux#2 implies that future buffer lookups in the currently running transaction will hit the transaction match code and not the buffer cache. Hence XBF_STALE and XFS_BLI_STALE will not be cleared unless the transaction initialises and logs the buffer with valid contents again. At which point, the buffer will be marked marked XBF_DONE again, so having XBF_DONE already set on the stale buffer is a moot point. 4. Rust-for-Linux#2 also implies that any concurrent access to that cluster buffer will block waiting on the buffer lock until the inode cluster has been fully freed and is no longer an active inode cluster buffer. 5. Rust-for-Linux#4 + #1 means that any future user of the disk range of that buffer will always see the range of disk blocks covered by the cluster buffer as not done, and hence must initialise the contents themselves. 6. Setting XBF_DONE in xfs_ifree_cluster() then means the unlinked inode precommit code will see a XBF_DONE buffer from the transaction match as it expects. It can then attach the stale but newly dirtied inode to the stale but newly dirtied cluster buffer without unexpected failures. The stale buffer will then sail through the journal and do the right thing with the attached stale inode during unpin. Hence the fix is just one line of extra code. The explanation of why we have to set XBF_DONE in xfs_ifree_cluster, OTOH, is long and complex.... Fixes: 82842fe ("xfs: fix AGF vs inode cluster buffer deadlock") Signed-off-by: Dave Chinner <dchinner@redhat.com> Tested-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
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It is possible to trigger a use-after-free by:
* attaching an fentry probe to __sock_release() and the probe calling the
bpf_get_socket_cookie() helper
* running traceroute -I 1.1.1.1 on a freshly booted VM
A KASAN enabled kernel will log something like below (decoded and stripped):
==================================================================
BUG: KASAN: slab-use-after-free in __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
Read of size 8 at addr ffff888007110dd8 by task traceroute/299
CPU: 2 PID: 299 Comm: traceroute Tainted: G E 6.10.0-rc2+ Rust-for-Linux#2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl (lib/dump_stack.c:117 (discriminator 1))
print_report (mm/kasan/report.c:378 mm/kasan/report.c:488)
? __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
kasan_report (mm/kasan/report.c:603)
? __sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
kasan_check_range (mm/kasan/generic.c:183 mm/kasan/generic.c:189)
__sock_gen_cookie (./arch/x86/include/asm/atomic64_64.h:15 ./include/linux/atomic/atomic-arch-fallback.h:2583 ./include/linux/atomic/atomic-instrumented.h:1611 net/core/sock_diag.c:29)
bpf_get_socket_ptr_cookie (./arch/x86/include/asm/preempt.h:94 ./include/linux/sock_diag.h:42 net/core/filter.c:5094 net/core/filter.c:5092)
bpf_prog_875642cf11f1d139___sock_release+0x6e/0x8e
bpf_trampoline_6442506592+0x47/0xaf
__sock_release (net/socket.c:652)
__sock_create (net/socket.c:1601)
...
Allocated by task 299 on cpu 2 at 78.328492s:
kasan_save_stack (mm/kasan/common.c:48)
kasan_save_track (mm/kasan/common.c:68)
__kasan_slab_alloc (mm/kasan/common.c:312 mm/kasan/common.c:338)
kmem_cache_alloc_noprof (mm/slub.c:3941 mm/slub.c:4000 mm/slub.c:4007)
sk_prot_alloc (net/core/sock.c:2075)
sk_alloc (net/core/sock.c:2134)
inet_create (net/ipv4/af_inet.c:327 net/ipv4/af_inet.c:252)
__sock_create (net/socket.c:1572)
__sys_socket (net/socket.c:1660 net/socket.c:1644 net/socket.c:1706)
__x64_sys_socket (net/socket.c:1718)
do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
Freed by task 299 on cpu 2 at 78.328502s:
kasan_save_stack (mm/kasan/common.c:48)
kasan_save_track (mm/kasan/common.c:68)
kasan_save_free_info (mm/kasan/generic.c:582)
poison_slab_object (mm/kasan/common.c:242)
__kasan_slab_free (mm/kasan/common.c:256)
kmem_cache_free (mm/slub.c:4437 mm/slub.c:4511)
__sk_destruct (net/core/sock.c:2117 net/core/sock.c:2208)
inet_create (net/ipv4/af_inet.c:397 net/ipv4/af_inet.c:252)
__sock_create (net/socket.c:1572)
__sys_socket (net/socket.c:1660 net/socket.c:1644 net/socket.c:1706)
__x64_sys_socket (net/socket.c:1718)
do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
Fix this by clearing the struct socket reference in sk_common_release() to cover
all protocol families create functions, which may already attached the
reference to the sk object with sock_init_data().
Fixes: c5dbb89 ("bpf: Expose bpf_get_socket_cookie to tracing programs")
Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/netdev/20240613194047.36478-1-kuniyu@amazon.com/T/
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: D. Wythe <alibuda@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240617210205.67311-1-ignat@cloudflare.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Jun 25, 2024
…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 Rust-for-Linux#2 fixes incorrect input and output netdevice in SRv6 prerouting hooks, from Jianguo Wu. Patch Rust-for-Linux#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 Rust-for-Linux#4-Rust-for-Linux#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>
metaspace
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Jun 25, 2024
…/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.10, take Rust-for-Linux#2 - Fix dangling references to a redistributor region if the vgic was prematurely destroyed. - Properly mark FFA buffers as released, ensuring that both parties can make forward progress.
metaspace
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Jun 25, 2024
into HEAD KVM/riscv fixes for 6.10, take Rust-for-Linux#2 - Fix compilation for KVM selftests
ojeda
pushed a commit
that referenced
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Jul 8, 2024
syzbot reported a lockdep violation involving bridge driver [1]
Make sure netdev_rename_lock is softirq safe to fix this issue.
[1]
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0 Not tainted
-----------------------------------------------------
syz-executor.2/9449 [HC0[0]:SC0[2]:HE0:SE0] is trying to acquire:
ffffffff8f5de668 (netdev_rename_lock.seqcount){+.+.}-{0:0}, at: rtnl_fill_ifinfo+0x38e/0x2270 net/core/rtnetlink.c:1839
and this task is already holding:
ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: br_port_slave_changelink+0x3d/0x150 net/bridge/br_netlink.c:1212
which would create a new lock dependency:
(&br->lock){+.-.}-{2:2} -> (netdev_rename_lock.seqcount){+.+.}-{0:0}
but this new dependency connects a SOFTIRQ-irq-safe lock:
(&br->lock){+.-.}-{2:2}
... which became SOFTIRQ-irq-safe at:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86
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
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758
fs_reclaim_acquire+0xaf/0x140 mm/page_alloc.c:3800
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]
kmalloc_trace_noprof+0x3d/0x2c0 mm/slub.c:4147
kmalloc_noprof include/linux/slab.h:660 [inline]
kzalloc_noprof include/linux/slab.h:778 [inline]
class_dir_create_and_add drivers/base/core.c:3255 [inline]
get_device_parent+0x2a7/0x410 drivers/base/core.c:3315
device_add+0x325/0xbf0 drivers/base/core.c:3645
netdev_register_kobject+0x17e/0x320 net/core/net-sysfs.c:2136
register_netdevice+0x11d5/0x19e0 net/core/dev.c:10375
nsim_init_netdevsim drivers/net/netdevsim/netdev.c:690 [inline]
nsim_create+0x647/0x890 drivers/net/netdevsim/netdev.c:750
__nsim_dev_port_add+0x6c0/0xae0 drivers/net/netdevsim/dev.c:1390
nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1446 [inline]
nsim_dev_reload_create drivers/net/netdevsim/dev.c:1498 [inline]
nsim_dev_reload_up+0x69b/0x8e0 drivers/net/netdevsim/dev.c:985
devlink_reload+0x478/0x870 net/devlink/dev.c:474
devlink_nl_reload_doit+0xbd6/0xe50 net/devlink/dev.c:586
genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0xb14/0xec0 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2585
___sys_sendmsg net/socket.c:2639 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
to a SOFTIRQ-irq-unsafe lock:
(netdev_rename_lock.seqcount){+.+.}-{0:0}
... which became SOFTIRQ-irq-unsafe at:
...
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
do_write_seqcount_begin_nested include/linux/seqlock.h:469 [inline]
do_write_seqcount_begin include/linux/seqlock.h:495 [inline]
write_seqlock include/linux/seqlock.h:823 [inline]
dev_change_name+0x184/0x920 net/core/dev.c:1229
do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2880
__rtnl_newlink net/core/rtnetlink.c:3696 [inline]
rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743
rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
__sys_sendto+0x3a4/0x4f0 net/socket.c:2192
__do_sys_sendto net/socket.c:2204 [inline]
__se_sys_sendto net/socket.c:2200 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2200
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(netdev_rename_lock.seqcount);
local_irq_disable();
lock(&br->lock);
lock(netdev_rename_lock.seqcount);
<Interrupt>
lock(&br->lock);
*** DEADLOCK ***
3 locks held by syz-executor.2/9449:
#0: ffffffff8f5e7448 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8f5e7448 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x1180 net/core/rtnetlink.c:6632
#1: ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline]
#1: ffff888060c64cb8 (&br->lock){+.-.}-{2:2}, at: br_port_slave_changelink+0x3d/0x150 net/bridge/br_netlink.c:1212
#2: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#2: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
#2: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: team_change_rx_flags+0x29/0x330 drivers/net/team/team_core.c:1767
the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (&br->lock){+.-.}-{2:2} {
HARDIRQ-ON-W at:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
br_add_if+0xb34/0xef0 net/bridge/br_if.c:682
do_set_master net/core/rtnetlink.c:2701 [inline]
do_setlink+0xe70/0x41f0 net/core/rtnetlink.c:2907
__rtnl_newlink net/core/rtnetlink.c:3696 [inline]
rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743
rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
__sys_sendto+0x3a4/0x4f0 net/socket.c:2192
__do_sys_sendto net/socket.c:2204 [inline]
__se_sys_sendto net/socket.c:2200 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2200
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
IN-SOFTIRQ-W at:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86
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
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758
fs_reclaim_acquire+0xaf/0x140 mm/page_alloc.c:3800
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]
kmalloc_trace_noprof+0x3d/0x2c0 mm/slub.c:4147
kmalloc_noprof include/linux/slab.h:660 [inline]
kzalloc_noprof include/linux/slab.h:778 [inline]
class_dir_create_and_add drivers/base/core.c:3255 [inline]
get_device_parent+0x2a7/0x410 drivers/base/core.c:3315
device_add+0x325/0xbf0 drivers/base/core.c:3645
netdev_register_kobject+0x17e/0x320 net/core/net-sysfs.c:2136
register_netdevice+0x11d5/0x19e0 net/core/dev.c:10375
nsim_init_netdevsim drivers/net/netdevsim/netdev.c:690 [inline]
nsim_create+0x647/0x890 drivers/net/netdevsim/netdev.c:750
__nsim_dev_port_add+0x6c0/0xae0 drivers/net/netdevsim/dev.c:1390
nsim_dev_port_add_all drivers/net/netdevsim/dev.c:1446 [inline]
nsim_dev_reload_create drivers/net/netdevsim/dev.c:1498 [inline]
nsim_dev_reload_up+0x69b/0x8e0 drivers/net/netdevsim/dev.c:985
devlink_reload+0x478/0x870 net/devlink/dev.c:474
devlink_nl_reload_doit+0xbd6/0xe50 net/devlink/dev.c:586
genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline]
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0xb14/0xec0 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2585
___sys_sendmsg net/socket.c:2639 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
INITIAL USE at:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
_raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:356 [inline]
br_add_if+0xb34/0xef0 net/bridge/br_if.c:682
do_set_master net/core/rtnetlink.c:2701 [inline]
do_setlink+0xe70/0x41f0 net/core/rtnetlink.c:2907
__rtnl_newlink net/core/rtnetlink.c:3696 [inline]
rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743
rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
__sys_sendto+0x3a4/0x4f0 net/socket.c:2192
__do_sys_sendto net/socket.c:2204 [inline]
__se_sys_sendto net/socket.c:2200 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2200
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
}
... key at: [<ffffffff94b9a1a0>] br_dev_setup.__key+0x0/0x20
the dependencies between the lock to be acquired
and SOFTIRQ-irq-unsafe lock:
-> (netdev_rename_lock.seqcount){+.+.}-{0:0} {
HARDIRQ-ON-W at:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
do_write_seqcount_begin_nested include/linux/seqlock.h:469 [inline]
do_write_seqcount_begin include/linux/seqlock.h:495 [inline]
write_seqlock include/linux/seqlock.h:823 [inline]
dev_change_name+0x184/0x920 net/core/dev.c:1229
do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2880
__rtnl_newlink net/core/rtnetlink.c:3696 [inline]
rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743
rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
__sys_sendto+0x3a4/0x4f0 net/socket.c:2192
__do_sys_sendto net/socket.c:2204 [inline]
__se_sys_sendto net/socket.c:2200 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2200
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
SOFTIRQ-ON-W at:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
do_write_seqcount_begin_nested include/linux/seqlock.h:469 [inline]
do_write_seqcount_begin include/linux/seqlock.h:495 [inline]
write_seqlock include/linux/seqlock.h:823 [inline]
dev_change_name+0x184/0x920 net/core/dev.c:1229
do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2880
__rtnl_newlink net/core/rtnetlink.c:3696 [inline]
rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743
rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
__sys_sendto+0x3a4/0x4f0 net/socket.c:2192
__do_sys_sendto net/socket.c:2204 [inline]
__se_sys_sendto net/socket.c:2200 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2200
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
INITIAL USE at:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
do_write_seqcount_begin_nested include/linux/seqlock.h:469 [inline]
do_write_seqcount_begin include/linux/seqlock.h:495 [inline]
write_seqlock include/linux/seqlock.h:823 [inline]
dev_change_name+0x184/0x920 net/core/dev.c:1229
do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2880
__rtnl_newlink net/core/rtnetlink.c:3696 [inline]
rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3743
rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
__sys_sendto+0x3a4/0x4f0 net/socket.c:2192
__do_sys_sendto net/socket.c:2204 [inline]
__se_sys_sendto net/socket.c:2200 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2200
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
INITIAL READ USE at:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline]
read_seqbegin include/linux/seqlock.h:772 [inline]
netdev_copy_name+0x168/0x2c0 net/core/dev.c:949
rtnl_fill_ifinfo+0x38e/0x2270 net/core/rtnetlink.c:1839
rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4073
rtmsg_ifinfo_event net/core/rtnetlink.c:4107 [inline]
rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4116
register_netdevice+0x1665/0x19e0 net/core/dev.c:10422
register_netdev+0x3b/0x50 net/core/dev.c:10512
loopback_net_init+0x73/0x150 drivers/net/loopback.c:217
ops_init+0x359/0x610 net/core/net_namespace.c:139
__register_pernet_operations net/core/net_namespace.c:1247 [inline]
register_pernet_operations+0x2cb/0x660 net/core/net_namespace.c:1320
register_pernet_device+0x33/0x80 net/core/net_namespace.c:1407
net_dev_init+0xfcd/0x10d0 net/core/dev.c:11956
do_one_initcall+0x248/0x880 init/main.c:1267
do_initcall_level+0x157/0x210 init/main.c:1329
do_initcalls+0x3f/0x80 init/main.c:1345
kernel_init_freeable+0x435/0x5d0 init/main.c:1578
kernel_init+0x1d/0x2b0 init/main.c:1467
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
}
... key at: [<ffffffff8f5de668>] netdev_rename_lock+0x8/0xa0
... acquired at:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline]
read_seqbegin include/linux/seqlock.h:772 [inline]
netdev_copy_name+0x168/0x2c0 net/core/dev.c:949
rtnl_fill_ifinfo+0x38e/0x2270 net/core/rtnetlink.c:1839
rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4073
rtmsg_ifinfo_event net/core/rtnetlink.c:4107 [inline]
rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4116
__dev_notify_flags+0xf7/0x400 net/core/dev.c:8816
__dev_set_promiscuity+0x152/0x5a0 net/core/dev.c:8588
dev_set_promiscuity+0x51/0xe0 net/core/dev.c:8608
team_change_rx_flags+0x203/0x330 drivers/net/team/team_core.c:1771
dev_change_rx_flags net/core/dev.c:8541 [inline]
__dev_set_promiscuity+0x406/0x5a0 net/core/dev.c:8585
dev_set_promiscuity+0x51/0xe0 net/core/dev.c:8608
br_port_clear_promisc net/bridge/br_if.c:135 [inline]
br_manage_promisc+0x505/0x590 net/bridge/br_if.c:172
nbp_update_port_count net/bridge/br_if.c:242 [inline]
br_port_flags_change+0x161/0x1f0 net/bridge/br_if.c:761
br_setport+0xcb5/0x16d0 net/bridge/br_netlink.c:1000
br_port_slave_changelink+0x135/0x150 net/bridge/br_netlink.c:1213
__rtnl_newlink net/core/rtnetlink.c:3689 [inline]
rtnl_newlink+0x169f/0x20a0 net/core/rtnetlink.c:3743
rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2585
___sys_sendmsg net/socket.c:2639 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
stack backtrace:
CPU: 0 PID: 9449 Comm: syz-executor.2 Not tainted 6.10.0-rc2-syzkaller-00249-gbe27b8965297 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_bad_irq_dependency kernel/locking/lockdep.c:2626 [inline]
check_irq_usage kernel/locking/lockdep.c:2865 [inline]
check_prev_add kernel/locking/lockdep.c:3138 [inline]
check_prevs_add kernel/locking/lockdep.c:3253 [inline]
validate_chain+0x4de0/0x5900 kernel/locking/lockdep.c:3869
__lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
seqcount_lockdep_reader_access include/linux/seqlock.h:72 [inline]
read_seqbegin include/linux/seqlock.h:772 [inline]
netdev_copy_name+0x168/0x2c0 net/core/dev.c:949
rtnl_fill_ifinfo+0x38e/0x2270 net/core/rtnetlink.c:1839
rtmsg_ifinfo_build_skb+0x18a/0x260 net/core/rtnetlink.c:4073
rtmsg_ifinfo_event net/core/rtnetlink.c:4107 [inline]
rtmsg_ifinfo+0x91/0x1b0 net/core/rtnetlink.c:4116
__dev_notify_flags+0xf7/0x400 net/core/dev.c:8816
__dev_set_promiscuity+0x152/0x5a0 net/core/dev.c:8588
dev_set_promiscuity+0x51/0xe0 net/core/dev.c:8608
team_change_rx_flags+0x203/0x330 drivers/net/team/team_core.c:1771
dev_change_rx_flags net/core/dev.c:8541 [inline]
__dev_set_promiscuity+0x406/0x5a0 net/core/dev.c:8585
dev_set_promiscuity+0x51/0xe0 net/core/dev.c:8608
br_port_clear_promisc net/bridge/br_if.c:135 [inline]
br_manage_promisc+0x505/0x590 net/bridge/br_if.c:172
nbp_update_port_count net/bridge/br_if.c:242 [inline]
br_port_flags_change+0x161/0x1f0 net/bridge/br_if.c:761
br_setport+0xcb5/0x16d0 net/bridge/br_netlink.c:1000
br_port_slave_changelink+0x135/0x150 net/bridge/br_netlink.c:1213
__rtnl_newlink net/core/rtnetlink.c:3689 [inline]
rtnl_newlink+0x169f/0x20a0 net/core/rtnetlink.c:3743
rtnetlink_rcv_msg+0x89b/0x1180 net/core/rtnetlink.c:6635
netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
netlink_sendmsg+0x8db/0xcb0 net/netlink/af_netlink.c:1905
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x221/0x270 net/socket.c:745
____sys_sendmsg+0x525/0x7d0 net/socket.c:2585
___sys_sendmsg net/socket.c:2639 [inline]
__sys_sendmsg+0x2b0/0x3a0 net/socket.c:2668
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3b3047cf29
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3b311740c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f3b305b4050 RCX: 00007f3b3047cf29
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000008
RBP: 00007f3b304ec074 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f3b305b4050 R15: 00007ffca2f3dc68
</TASK>
Fixes: 0840556 ("net: Protect dev->name by seqlock.")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ojeda
pushed a commit
that referenced
this issue
Jul 8, 2024
…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
#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>
ojeda
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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] #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2] #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2] #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2] #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2] #10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2] #11 dio_complete at ffffffff8c2b9fa7 #12 do_blockdev_direct_IO at ffffffff8c2bc09f #13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2] #14 generic_file_direct_write at ffffffff8c1dcf14 #15 __generic_file_write_iter at ffffffff8c1dd07b #16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2] #17 aio_write at ffffffff8c2cc72e #18 kmem_cache_alloc at ffffffff8c248dde #19 do_io_submit at ffffffff8c2ccada #20 do_syscall_64 at ffffffff8c004984 #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>
ojeda
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…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains two Netfilter fixes for net: Patch #1 fixes CONFIG_SYSCTL=n for a patch coming in the previous PR to move the sysctl toggle to enable SRv6 netfilter hooks from nf_conntrack to the core, from Jianguo Wu. Patch #2 fixes a possible pointer leak to userspace due to insufficient validation of NFT_DATA_VALUE. Linus found this pointer leak to userspace via zdi-disclosures@ and forwarded the notice to Netfilter maintainers, he appears as reporter because whoever found this issue never approached Netfilter maintainers neither via security@ nor in private. netfilter pull request 24-06-27 * tag 'nf-24-06-27' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nf_tables: fully validate NFT_DATA_VALUE on store to data registers netfilter: fix undefined reference to 'netfilter_lwtunnel_*' when CONFIG_SYSCTL=n ==================== Link: https://patch.msgid.link/20240626233845.151197-1-pablo@netfilter.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
ojeda
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This fixes the following deadlock introduced by 39a92a5 ("bluetooth/l2cap: sync sock recv cb and release") ============================================ WARNING: possible recursive locking detected 6.10.0-rc3-g4029dba6b6f1 #6823 Not tainted -------------------------------------------- kworker/u5:0/35 is trying to acquire lock: ffff888002ec2510 (&chan->lock#2/1){+.+.}-{3:3}, at: l2cap_sock_recv_cb+0x44/0x1e0 but task is already holding lock: ffff888002ec2510 (&chan->lock#2/1){+.+.}-{3:3}, at: l2cap_get_chan_by_scid+0xaf/0xd0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&chan->lock#2/1); lock(&chan->lock#2/1); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by kworker/u5:0/35: #0: ffff888002b8a940 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work+0x750/0x930 #1: ffff888002c67dd0 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work+0x44e/0x930 #2: ffff888002ec2510 (&chan->lock#2/1){+.+.}-{3:3}, at: l2cap_get_chan_by_scid+0xaf/0xd0 To fix the original problem this introduces l2cap_chan_lock at l2cap_conless_channel to ensure that l2cap_sock_recv_cb is called with chan->lock held. Fixes: 89e856e ("bluetooth/l2cap: sync sock recv cb and release") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
ojeda
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Jul 8, 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+ #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+ #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
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When tries to demote 1G hugetlb folios, a lockdep warning is observed: ============================================ WARNING: possible recursive locking detected 6.10.0-rc6-00452-ga4d0275fa660-dirty #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 #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>
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…/git/gregkh/tty Pull tty / serial updates from Greg KH: "Here is a small set of tty and serial driver updates for 6.11-rc1. Not much happened this cycle, unlike the previous kernel release which had lots of "excitement" in this part of the kernel. Included in here are the following changes: - dt binding updates for new platforms - 8250 driver updates - various small serial driver fixes and updates - printk/console naming and matching attempt #2 (was reverted for 6.10-final, should be good to go this time around, acked by the relevant maintainers). All of these have been in linux-next for a while with no reported issues" * tag 'tty-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (22 commits) Documentation: kernel-parameters: Add DEVNAME:0.0 format for serial ports serial: core: Add serial_base_match_and_update_preferred_console() printk: Add match_devname_and_update_preferred_console() serial: sc16is7xx: hardware reset chip if reset-gpios is defined in DT dt-bindings: serial: sc16is7xx: add reset-gpios dt-bindings: serial: vt8500-uart: convert to json-schema serial: 8250_platform: Explicitly show we initialise ISA ports only once tty: add missing MODULE_DESCRIPTION() macros dt-bindings: serial: mediatek,uart: add MT7988 serial: sh-sci: Add support for RZ/V2H(P) SoC dt-bindings: serial: Add documentation for Renesas RZ/V2H(P) (R9A09G057) SCIF support dt-bindings: serial: renesas,scif: Make 'interrupt-names' property as required dt-bindings: serial: renesas,scif: Validate 'interrupts' and 'interrupt-names' dt-bindings: serial: renesas,scif: Move ref for serial.yaml at the end riscv: dts: starfive: jh7110: Add the core reset and jh7110 compatible for uarts serial: 8250_dw: Use reset array API to get resets dt-bindings: serial: snps-dw-apb-uart: Add one more reset signal for StarFive JH7110 SoC serial: 8250: Extract platform driver serial: 8250: Extract RSA bits serial: imx: stop casting struct uart_port to struct imx_port ...
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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+ #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+ #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>
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In z_erofs_get_gbuf(), the current task may be migrated to another CPU between `z_erofs_gbuf_id()` and `spin_lock(&gbuf->lock)`. Therefore, z_erofs_put_gbuf() will trigger the following issue which was found by stress test: <2>[772156.434168] kernel BUG at fs/erofs/zutil.c:58! .. <4>[772156.435007] <4>[772156.439237] CPU: 0 PID: 3078 Comm: stress Kdump: loaded Tainted: G E 6.10.0-rc7+ #2 <4>[772156.439239] Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 1.0.0 01/01/2017 <4>[772156.439241] pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) <4>[772156.439243] pc : z_erofs_put_gbuf+0x64/0x70 [erofs] <4>[772156.439252] lr : z_erofs_lz4_decompress+0x600/0x6a0 [erofs] .. <6>[772156.445958] stress (3127): drop_caches: 1 <4>[772156.446120] Call trace: <4>[772156.446121] z_erofs_put_gbuf+0x64/0x70 [erofs] <4>[772156.446761] z_erofs_lz4_decompress+0x600/0x6a0 [erofs] <4>[772156.446897] z_erofs_decompress_queue+0x740/0xa10 [erofs] <4>[772156.447036] z_erofs_runqueue+0x428/0x8c0 [erofs] <4>[772156.447160] z_erofs_readahead+0x224/0x390 [erofs] .. Fixes: f36f301 ("erofs: rename per-CPU buffers to global buffer pool and make it configurable") Cc: <stable@vger.kernel.org> # 6.10+ Reviewed-by: Chunhai Guo <guochunhai@vivo.com> Reviewed-by: Sandeep Dhavale <dhavale@google.com> Reviewed-by: Chao Yu <chao@kernel.org> Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com> Link: https://lore.kernel.org/r/20240722035110.3456740-1-hsiangkao@linux.alibaba.com
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This just standardizes the use of MIN() and MAX() macros, with the very traditional semantics. The goal is to use these for C constant expressions and for top-level / static initializers, and so be able to simplify the min()/max() macros. These macro names were used by various kernel code - they are very traditional, after all - and all such users have been fixed up, with a few different approaches: - trivial duplicated macro definitions have been removed Note that 'trivial' here means that it's obviously kernel code that already included all the major kernel headers, and thus gets the new generic MIN/MAX macros automatically. - non-trivial duplicated macro definitions are guarded with #ifndef This is the "yes, they define their own versions, but no, the include situation is not entirely obvious, and maybe they don't get the generic version automatically" case. - strange use case #1 A couple of drivers decided that the way they want to describe their versioning is with #define MAJ 1 #define MIN 2 #define DRV_VERSION __stringify(MAJ) "." __stringify(MIN) which adds zero value and I just did my Alexander the Great impersonation, and rewrote that pointless Gordian knot as #define DRV_VERSION "1.2" instead. - strange use case #2 A couple of drivers thought that it's a good idea to have a random 'MIN' or 'MAX' define for a value or index into a table, rather than the traditional macro that takes arguments. These values were re-written as C enum's instead. The new function-line macros only expand when followed by an open parenthesis, and thus don't clash with enum use. Happily, there weren't really all that many of these cases, and a lot of users already had the pattern of using '#ifndef' guarding (or in one case just using '#undef MIN') before defining their own private version that does the same thing. I left such cases alone. Cc: David Laight <David.Laight@aculab.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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…pinlock_t'
This lock is acquired under irq_desc::lock with interrupts disabled.
When PREEMPT_RT is enabled, 'spinlock_t' becomes preemptible, which results
in invalid lock acquire context;
[ BUG: Invalid wait context ]
swapper/0/1 is trying to lock:
ffff0000008fed30 (&ctl->lock){....}-{3:3}, at: meson_gpio_irq_update_bits0
other info that might help us debug this:
context-{5:5}
3 locks held by swapper/0/1:
#0: ffff0000003cd0f8 (&dev->mutex){....}-{4:4}, at: __driver_attach+0x90c
#1: ffff000004714650 (&desc->request_mutex){+.+.}-{4:4}, at: __setup_irq0
#2: ffff0000047144c8 (&irq_desc_lock_class){-.-.}-{2:2}, at: __setup_irq0
stack backtrace:
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.9.9-sdkernel #1
Call trace:
_raw_spin_lock_irqsave+0x60/0x88
meson_gpio_irq_update_bits+0x34/0x70
meson8_gpio_irq_set_type+0x78/0xc4
meson_gpio_irq_set_type+0x30/0x60
__irq_set_trigger+0x60/0x180
__setup_irq+0x30c/0x6e0
request_threaded_irq+0xec/0x1a4
Fixes: 215f4cc ("irqchip/meson: Add support for gpio interrupt controller")
Signed-off-by: Arseniy Krasnov <avkrasnov@salutedevices.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240729131850.3015508-1-avkrasnov@salutedevices.com
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…git/netfilter/nf
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net:
Fix a possible null-ptr-deref sometimes triggered by iptables-restore at
boot time. Register iptables {ipv4,ipv6} nat table pernet in first place
to fix this issue. Patch #1 and #2 from Kuniyuki Iwashima.
netfilter pull request 24-07-31
* tag 'nf-24-07-31' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: iptables: Fix potential null-ptr-deref in ip6table_nat_table_init().
netfilter: iptables: Fix null-ptr-deref in iptable_nat_table_init().
====================
Link: https://patch.msgid.link/20240731213046.6194-1-pablo@netfilter.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Aug 14, 2024
Currently the dma debugging code can end up indirectly calling printk under the radix_lock. This happens when a radix tree node allocation fails. This is a problem because the printk code, when used together with netconsole, can end up inside the dma debugging code while trying to transmit a message over netcons. This creates the possibility of either a circular deadlock on the same CPU, with that CPU trying to grab the radix_lock twice, or an ABBA deadlock between different CPUs, where one CPU grabs the console lock first and then waits for the radix_lock, while the other CPU is holding the radix_lock and is waiting for the console lock. The trace captured by lockdep is of the ABBA variant. -> Rust-for-Linux#2 (&dma_entry_hash[i].lock){-.-.}-{2:2}: _raw_spin_lock_irqsave+0x5a/0x90 debug_dma_map_page+0x79/0x180 dma_map_page_attrs+0x1d2/0x2f0 bnxt_start_xmit+0x8c6/0x1540 netpoll_start_xmit+0x13f/0x180 netpoll_send_skb+0x20d/0x320 netpoll_send_udp+0x453/0x4a0 write_ext_msg+0x1b9/0x460 console_flush_all+0x2ff/0x5a0 console_unlock+0x55/0x180 vprintk_emit+0x2e3/0x3c0 devkmsg_emit+0x5a/0x80 devkmsg_write+0xfd/0x180 do_iter_readv_writev+0x164/0x1b0 vfs_writev+0xf9/0x2b0 do_writev+0x6d/0x110 do_syscall_64+0x80/0x150 entry_SYSCALL_64_after_hwframe+0x4b/0x53 -> #0 (console_owner){-.-.}-{0:0}: __lock_acquire+0x15d1/0x31a0 lock_acquire+0xe8/0x290 console_flush_all+0x2ea/0x5a0 console_unlock+0x55/0x180 vprintk_emit+0x2e3/0x3c0 _printk+0x59/0x80 warn_alloc+0x122/0x1b0 __alloc_pages_slowpath+0x1101/0x1120 __alloc_pages+0x1eb/0x2c0 alloc_slab_page+0x5f/0x150 new_slab+0x2dc/0x4e0 ___slab_alloc+0xdcb/0x1390 kmem_cache_alloc+0x23d/0x360 radix_tree_node_alloc+0x3c/0xf0 radix_tree_insert+0xf5/0x230 add_dma_entry+0xe9/0x360 dma_map_page_attrs+0x1d2/0x2f0 __bnxt_alloc_rx_frag+0x147/0x180 bnxt_alloc_rx_data+0x79/0x160 bnxt_rx_skb+0x29/0xc0 bnxt_rx_pkt+0xe22/0x1570 __bnxt_poll_work+0x101/0x390 bnxt_poll+0x7e/0x320 __napi_poll+0x29/0x160 net_rx_action+0x1e0/0x3e0 handle_softirqs+0x190/0x510 run_ksoftirqd+0x4e/0x90 smpboot_thread_fn+0x1a8/0x270 kthread+0x102/0x120 ret_from_fork+0x2f/0x40 ret_from_fork_asm+0x11/0x20 This bug is more likely than it seems, because when one CPU has run out of memory, chances are the other has too. The good news is, this bug is hidden behind the CONFIG_DMA_API_DEBUG, so not many users are likely to trigger it. Signed-off-by: Rik van Riel <riel@surriel.com> Reported-by: Konstantin Ovsepian <ovs@meta.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
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linkwatch_event() grabs possibly very contended RTNL mutex.
system_wq is not suitable for such work.
Inspired by many noisy syzbot reports.
3 locks held by kworker/0:7/5266:
#0: ffff888015480948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
#0: ffff888015480948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
Rust-for-Linux#1: ffffc90003f6fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
Rust-for-Linux#2: ffffffff8fa6f208 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276
Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 1da177e ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20240805085821.1616528-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.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+ Rust-for-Linux#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 Rust-for-Linux#1: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0 Rust-for-Linux#2: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130 Rust-for-Linux#3: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x28b/0x9f0 Rust-for-Linux#4: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0xf9/0x260 Rust-for-Linux#5: ffff888102650d98 (slock-AF_INET/1){+.-.}-{2:2}, at: tcp_v4_rcv+0x1848/0x1e10 Rust-for-Linux#6: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x4b/0xbc0 Rust-for-Linux#7: ffffffff822ac220 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x17a/0x1130 Rust-for-Linux#8: ffffffff822ac1e0 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0xcc/0x1450 Rust-for-Linux#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+ Rust-for-Linux#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>
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…on array The out-of-bounds access is reported by UBSAN: [ 0.000000] UBSAN: array-index-out-of-bounds in ../arch/riscv/kernel/vendor_extensions.c:41:66 [ 0.000000] index -1 is out of range for type 'riscv_isavendorinfo [32]' [ 0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.11.0-rc2ubuntu-defconfig #2 [ 0.000000] Hardware name: riscv-virtio,qemu (DT) [ 0.000000] Call Trace: [ 0.000000] [<ffffffff94e078ba>] dump_backtrace+0x32/0x40 [ 0.000000] [<ffffffff95c83c1a>] show_stack+0x38/0x44 [ 0.000000] [<ffffffff95c94614>] dump_stack_lvl+0x70/0x9c [ 0.000000] [<ffffffff95c94658>] dump_stack+0x18/0x20 [ 0.000000] [<ffffffff95c8bbb2>] ubsan_epilogue+0x10/0x46 [ 0.000000] [<ffffffff95485a82>] __ubsan_handle_out_of_bounds+0x94/0x9c [ 0.000000] [<ffffffff94e09442>] __riscv_isa_vendor_extension_available+0x90/0x92 [ 0.000000] [<ffffffff94e043b6>] riscv_cpufeature_patch_func+0xc4/0x148 [ 0.000000] [<ffffffff94e035f8>] _apply_alternatives+0x42/0x50 [ 0.000000] [<ffffffff95e04196>] apply_boot_alternatives+0x3c/0x100 [ 0.000000] [<ffffffff95e05b52>] setup_arch+0x85a/0x8bc [ 0.000000] [<ffffffff95e00ca0>] start_kernel+0xa4/0xfb6 The dereferencing using cpu should actually not happen, so remove it. Fixes: 23c996f ("riscv: Extend cpufeature.c to detect vendor extensions") Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240814192619.276794-1-alexghiti@rivosinc.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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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 #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 #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 #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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Unstable features (including language, library, tools...) we currently use.
See as well:
corewanted features & bugfixes #514allocwanted features & bugfixes #408stdwanted features & bugfixes #572rustcwanted features & bugfixes #355rustdocwanted features & bugfixes #350rustfmtwanted features & bugfixes #398bindgenwanted features & bugfixes #353rustupwanted features & bugfixes #396paholewanted features & bugfixes #1096rustc_codegen_gccwanted features & bugfixes #1098Required (we almost certainly want them)
cfg(no_fp_fmt_parse).core).cfg(no_global_oom_handling).alloc).cfg(no_rc).alloc).alloc: add unstable cfg featuresno_rcandno_syncrust-lang/rust#89891).cfg(no_sync).alloc).alloc: add unstable cfg featuresno_rcandno_syncrust-lang/rust#89891).Clippy's configuration file.
Clippy's
CLIPPY_CONF_DIRenvironment variable..clippy.toml).feature(asm_const)with support for raw pointers.feature(asm_goto).asm!rust-lang/rust#119365). Stabilization waiting on getting some usage in the Linux kernel (https://rust-lang.zulipchat.com/#narrow/stream/425075-rust-for-linux/topic/asm-goto.20stabilization/near/447335751).feature(const_mut_refs)&feature(const_refs_to_static).&mut Tin const contexts (const_mut_refs) rust-lang/rust#57349 and Tracking Issue for const_refs_to_static rust-lang/rust#119618.const TABLEs (settingownerfield toTHIS_MODULE), as well asrust/kernel/module_param.rs(in therustbranch).const_mut_refsstabilized in 1.83 (Stabilize&mut(and*mut) as well as&Cell(and*const Cell) in const rust-lang/rust#129195; reference: const_eval: update for const_mut_refs and const_refs_to_cell stabilization rust-lang/reference#1590);const_refs_to_staticstabilization proposal at Proposal: stabilizeconst_refs_to_staticrust-lang/rust#128183. It is one of the subfeatures ofconst_fn.VTABLEtest case (tests/ui/consts/const-ref-to-static-linux-vtable.rs): const_mut_refs: allow mutable pointers to statics rust-lang/rust#120932 (1.78).feature(derive_smart_pointer)(i.e.derive(SmartPointer)).derive(SmartPointer)rust-lang/rust#123430.Arc.Arc.derive(SmartPointer)rust-lang/rust#123472.feature(pin_coerce_unsized_trait), one of the solutions for the unsoundness issue in the main RFC): PinCoerceUnsized trait into core rust-lang/rust#125048 (1.82).derive(SmartPtr)rust-lang/rust#129104.#[pointee]attribute is required even if there is only one generic parameter rust-lang/rust#129465.feature(doc_cfg).#[doc(cfg(…))],#[doc(cfg_hide(…))]anddoc_auto_cfgrust-lang/rust#43781.rust/kernel/lib.rs.doc(cfg(...))from thecfg(...)(to avoid duplication) etc. See also Consider allowing to build docs for the current kernel config #447.feature(impl_trait_in_assoc_type).rnull(https://lore.kernel.org/rust-for-linux/20240313110515.70088-5-nmi@metaspace.dk/).feature(register_tool).#![register_tool]rust-lang/rust#66079.klintExperimental PR for introducing klint #958.-Zbinary_dep_depinfo=y.-Zbranch-protection.-Z branch-protectionrust-lang/rust#113369.CONFIG_ARM64_BTI_KERNELetc.-Zcf-protection-- see https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/.60-Zbranch-protection.60.20stability/near/391152508.-Zcf-protection=branch(CET).CONFIG_X86_KERNEL_IBT(https://lore.kernel.org/rust-for-linux/20231009224347.2076221-1-mmaurer@google.com/).-Zdebuginfo-compression(includingzstdsupport in Rust binaries' bundled LLVM).-Zdebuginfo-compressionrust-lang/rust#120953.zstdsupport is used in Android, where it currently warns, see commit dbef181 ("kbuild: rust: use-Zdebuginfo-compression").-Zdirect-access-external-data={yes,no}(Clang's-fdirect-access-external-data).-Zdirect-access-external-datarust-lang/rust#127488.-Z direct-access-external-datacmdline flag forrustcrust-lang/rust#119162).-Zdwarf-version.-Zfixed-x18.-Zfixed-x18rust-lang/rust#124655.-Zfunction-return=thunk-extern.-Zfunction-returnrust-lang/rust#116853.CONFIG_MITIGATION_RETHUNK.-Zfunction-return={keep,thunk-extern}option rust-lang/rust#116892).-Zinstrument-mcount.#[coverage]rust-lang/rust#84605 (#[no_coverage]).-Zno-jump-tables.no-jump-tablesrust-lang/rust#116592.CONFIG_X86_KERNEL_IBT(https://lore.kernel.org/rust-for-linux/20231009224347.2076221-1-mmaurer@google.com/).-Zno-jump-tablesrust-lang/rust#105812 (1.68).-Zpatchable-function-entrysupport (GCC's and Clang's-fpatchable-function-entry), as well as thepatchable_function_entryfunction attribute.-Zrandomize-layout(and-Zlayout-seed=<seed>).-Z randomize-layoutrust-lang/rust#106764.CONFIG_RANDSTRUCT*).-Zsanitizer=kcfi&-Zsanitizer-cfi-normalize-integers(KCFI).CONFIG_CFI_CLANG).-Cpanic=abortuntil LLVM'sinvokesupports KCFI bundles: CFI: Abstract Closures and Coroutines rust-lang/rust#123106 (comment).-Ztune-cpu=generic.Makefile.rustdoc's--generate-link-to-definition(-Zunstable-options).[references]link from doc/source view could be nice to get).rustdoc's--no-run(-Zunstable-options).--no-runrust-lang/rust#87022.rustdoc's--test-builder(-Zunstable-options).--test-builderrust-lang/rust#102981.ignore, etc.) -- discussed with @GuillaumeGomez, we will write an issue with details about what could work for us.Remaining target features unknown to
rustc.#[target_feature]rust-lang/rust#44839.Target specification file or enough command-line flags to replace it.
-Cglobal-target-feature=) could be useful, i.e. a target feature that is required to be set the same way for all compilation units (without requiring a new target). In other words, using flags to create combinations of targets instead of requiring a different for each combination. See-Cfixed-x18discussion as well.Nice to have (not critical, we could workaround if needed, etc.)
As many required bits done in the Rust version of the upcoming Debian Stable (Trixie).
--extern force:.--extern forcerust-lang/rust#111302.allocextern to allow "empty" Rust files")).new_uninitis dropped. There may be other workarounds. Added as unstable in 1.71 (Addforceoption for--externflag rust-lang/rust#109421).feature(associated_type_defaults).file_operations.rsto simplify boilerplate needed by drivers, as well aspci.rs(e.g. https://lore.kernel.org/rust-for-linux/20240520172554.182094-10-dakr@redhat.com/).feature(box_uninit_write).box_uninit_writerust-lang/rust#129397.unsafeblock inBox<T>::new()(BoxExt).feature(const_trait_impl).impl const Trait for Tyand~const(tilde const) syntax rust-lang/rust#67792.rust/kernel/driver.rs(e.g. see_new_id_array!,define_id_array!anddefine_id_table!in https://lore.kernel.org/rust-for-linux/20240520172554.182094-3-dakr@redhat.com/).feature(c_size_t)# rust-lang/rust#88345.rust/kernel/file.rs(so far, but could be anywhere in the abstractions).core_ffi_cgot stabilized in 1.64 (Stabilizecore::ffi:c_*and re-export instd::ffirust-lang/rust#98315) andc_{s,}size_tare now incore::ffisince 1.61 (Provide C FFI types via core::ffi, not just in std rust-lang/rust#94503). We can always go back toc_types.rs.feature(duration_constants).rust/kernel/delay.rs.TimeUnitsto do things like2.seconds()). We can always use our own constants.feature(ptr_metadata)(core::ptr::metadataandcore::ptr::from_raw_parts_mutfunctions).Arc, and potentially byimpl_zeroable!to include pointers to DSTs when their metadata isZeroablevia thePointeetrait.-Zcrate-attr.-Zfunction-sections(inrustc, it applies to data too).rustc: rust-lang/rust@6b130e3).Makefile(underCONFIG_LD_DEAD_CODE_DATA_ELIMINATION, which is experimental so far).-Zub-checks(cfg(ub_checks)).feature(ub_checks)and-Zub-checksrust-lang/rust#123499.-Cdebug-assertions, but not stabilizing this means one cannot enable/disable each of them independently.-Zunpretty=expanded.RUSTC_BOOTSTRAP=1only for the target that uses it, if needed).-Zuse-sync-unwind=n.nremains the default.Low priority (we will likely not use them in the end)
feature(allocator_api).allocfork, but we are likely dropping it (https://lore.kernel.org/rust-for-linux/20240328013603.206764-1-wedsonaf@gmail.com/); otherwise: still quite open.feature(coerce_unsized)&feature(unsize)(core::ops::CoerceUnsizedandcore::marker::Unsizetraits).Arc.feature(derive_smart_pointer)instead to avoid depending onArc's needed features; otherwise: "theCoerceUnsizedtrait is unstable and we wish to revisit its design before stabilizing, so for now only stdlib types can be unsized" + there are unsoundness issues, seePinis unsound due to transitive effects ofCoerceUnsizedrust-lang/rust#68015 and APinunsoundness involving animpl DerefMut for Pin<&dyn LocalTrait>rust-lang/rust#85099. See https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/rust-for-linux.20custom.20arc.20unstable.20feature.20requirements.feature(dispatch_from_dyn)(core::ops::DispatchFromDyntrait).Arc.feature(derive_smart_pointer)instead to avoid depending onArc's needed features; otherwise: see https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/rust-for-linux.20custom.20arc.20unstable.20feature.20requirements.feature(pointer_is_aligned)(is_aligned_to).FromBytes(VFS abstractions, Useis_aligned_toinFromBytesonce it's available #1038).is_aligned()) got stabilized in 1.79 (stabilize ptr.is_aligned, move ptr.is_aligned_to to a new feature gate rust-lang/rust#121948).is_aligned_to()may be stabilized, but it needs to be justified.feature(more_fallible_allocation_methods).more_fallible_allocation_methodsrust-lang/rust#86942.alloc.allocfork, but we are likely dropping it (https://lore.kernel.org/rust-for-linux/20240328013603.206764-1-wedsonaf@gmail.com/); otherwise: unknown.feature(receiver_trait)(core::ops::Receivertrait).Arc.feature(derive_smart_pointer)instead to avoid depending onArc's needed features; otherwise: see https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/rust-for-linux.20custom.20arc.20unstable.20feature.20requirements. Another potential solution might befeature(arbitrary_self_types)(Tracking issue for RFC 3519:arbitrary_self_typesrust-lang/rust#44874), though it has different tradeoffs.__rust_no_alloc_shim_is_unstable.rust/kernel/allocator.rsat the moment, but we will not need when the allocator series goes in: https://lore.kernel.org/rust-for-linux/6HIL4hSg3hOCh5IDDOtdEaEy89ZksSJmSLNiKrSvpu2Q78wA5KdrCCrcPSD_p4jB7IlmVRyVBnvBllU4irzuYgpQJOBtwUInAKdOibtRjVc=@protonmail.com/, Björn says:Done (stabilized, not needed anymore, etc.)
--check-cfg.--check-cfgoption rust-lang/rust#123501).cfgs): Limit the number of names and values in check-cfg diagnostics rust-lang/rust#121202 (1.78).CARGO_CRATE_NAMEinstead ofCARGOas a better heuristic for Cargo diagnostics): Use better heuristic for printing Cargo specific diagnostics rust-lang/rust#121237 (1.78).feature(alloc_error_handler).no_global_oom_handling.feature(asm_const).asm_construst-lang/rust#128570).feature(bench_black_box).std::hint::black_boxrust-lang/rust#64102.samples/rust/rust_stack_probing.rs.feature(concat_idents).concat_identsrust-lang/rust#29599.drivers/android/defs.rsin the past, nothing now.pastecrate is an alternative (or, in general, generating code). We ended up using a proc macro on our side Re-implement concat_idents! in libmacros #826.feature(const_fn_transmute).rust/kernel/str.rs.const_fn_transmute,const_fn_unionrust-lang/rust#85769). It is one of the subfeatures ofconst_fn.feature(const_fn_trait_bound).const fnrust-lang/rust#57563.rust/kernel/file_operations.rsandrust/kernel/module_param.rs.const_fn.feature(const_maybe_uninit_zeroed).const_maybe_uninit_zeroedrust-lang/rust#91850.const_maybe_uninit_zeroedandconst_mem_zeroedrust-lang/rust#116218).feature(const_panic).rust/kernel/print.rs.const_panicrust-lang/rust#89508). It is one of the subfeatures ofconst_fn.feature(const_ptr_offset_from).rust/kernel/driver.rs.const_ptr_offset_from. rust-lang/rust#96240).feature(const_raw_ptr_deref)rust/kernel/str.rs.const_fn_transmutesince that was getting stabilized sooner.feature(const_refs_to_cell).const_refs_to_cellrust-lang/rust#80384.rust/kernel/driver.rs,offset_of!(iffeature(offset_of)does not pan out).&mut(and*mut) as well as&Cell(and*const Cell) in const rust-lang/rust#129195, reference: const_eval: update for const_mut_refs and const_refs_to_cell stabilization rust-lang/reference#1590).feature(const_unreachable_unchecked).unreachable_uncheckedrust-lang/rust#53188.rust/kernel/str.rs.unreachable_uncheckedasconst fnrust-lang/rust#89509). It is one of the subfeatures ofconst_fn.feature(core_ffi_c)module!, etc.core::ffi:c_*and re-export instd::ffirust-lang/rust#98315).feature(core_panic).rust/build_assert.rs.panic!("{}", msg)(2021 edition, allowed in const context since Allowpanic!("{}", computed_str)in const fn. rust-lang/rust#88954).feature(explicit_generic_args_with_impl_trait)explicit_generic_args_with_impl_traitrust-lang/rust#83701.pinned-init.feature(generic_associated_types).rust/kernel/types.rs(PointerWrapper),rust/kernel/file_operations.rs(IoctlHandler).feature(global_asm).rust/module.rsproc macro.module.rs, use codegen instead #77.feature(let_else).let_elsehelps naturally with that (when applicable).rust/macros/paste.rsand potentially everywhere.let elserust-lang/rust#93628).feature(maybe_uninit_extra).#![feature(maybe_uninit_extra,const_maybe_uninit_write)]rust-lang/rust#63567.rust/kernel/miscdev.rs.maybe_uninit_extrarust-lang/rust#92768) (non-const only, which is the only part we need).feature(new_uninit).pin-initAPIfeature(new_uninit)rust-lang/rust#129401). The feature was split during stabilization, with a couple new features were created for things not to be stabilized yet:box_uninit_write(which we could use to avoid anunsafeblock, but it was replaced for the time being) andnew_zeroed_alloc.feature(offset_of)(single-field, i.e. noenum, no nested).#![feature(offset_of)]rust-lang/rust#106655.rust/kernel/workqueue.rsandkernel/kasync/executor/workqueue.rs(https://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git/commit/?h=for-6.7-rust-bindings&id=7324b88975c525a013ae0db747df97924ce80675).feature(offset_of_nested).feature(pin_macro).core::pin::pin!rust-lang/rust#93178.stack_pin_init!andstack_try_pin_init!.::{core,std}::pin::pin!rust-lang/rust#103800).feature(try_reserve).try_reserve: RFC 2116 fallible collection allocation rust-lang/rust#48043.rust/kernel/lib.rs.-Zallow-features.-Zbuild-std.rusttesttarget, back when we had a customalloc).allocanmore. The actual progress is not clear. Seestdwanted features & bugfixes #572.-Zsplit-dwarf-kind=split.splitstops being the default.splitis the default, we will not need it.-Zsymbol-mangling-version=v0.rust/exports.c.The text was updated successfully, but these errors were encountered: