bnxt_en: Issue PCIe FLR in kdump kernel to cleanup pending DMAs.

[ Upstream commit 8743db4 ]

If crashed kernel does not shutdown the NIC properly, PCIe FLR
is required in the kdump kernel in order to initialize all the
functions properly.

Fixes: d629522 ("bnxt_en: Reduce memory usage when running in kdump kernel.")
Signed-off-by: Vasundhara Volam <vasundhara-v.volam@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -11712,6 +11712,14 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (version_printed++ == 0)
 		pr_info("%s", version);
 
+	/* Clear any pending DMA transactions from crash kernel
+	 * while loading driver in capture kernel.
+	 */
+	if (is_kdump_kernel()) {
+		pci_clear_master(pdev);
+		pcie_flr(pdev);
+	}
+
 	max_irqs = bnxt_get_max_irq(pdev);
 	dev = alloc_etherdev_mq(sizeof(*bp), max_irqs);
 	if (!dev)