[PATCH AUTOSEL 5.5 59/66] bnxt_en: Issue PCIe FLR in kdump kernel to cleanup pending DMAs.

From: Sasha Levin
Date: Mon Mar 02 2020 - 21:47:33 EST


From: Vasundhara Volam <vasundhara-v.volam@xxxxxxxxxxxx>

[ Upstream commit 8743db4a9acfd51f805ac0c87bcaae92c42d1061 ]

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: d629522e1d66 ("bnxt_en: Reduce memory usage when running in kdump kernel.")
Signed-off-by: Vasundhara Volam <vasundhara-v.volam@xxxxxxxxxxxx>
Signed-off-by: Michael Chan <michael.chan@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/broadcom/bnxt/bnxt.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 1a90118370ea1..cc86038b1d96b 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -11775,6 +11775,14 @@ 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)
--
2.20.1