Subject: [PATCH AUTOSEL 4.19 2/5] bnx2x: fix page fault following EEH recovery

From: Sasha Levin <[email-masked]>
Date: Tue, 29 Aug 2023 09:34:03 -0400

From: David Christensen <[email-masked]>

[ Upstream commit 7ebe4eda4265642859507d1b3ca330d8c196cfe5 ]

In the last step of the EEH recovery process, the EEH driver calls into
bnx2x_io_resume() to re-initialize the NIC hardware via the function
bnx2x_nic_load().  If an error occurs during bnx2x_nic_load(), OS and
hardware resources are released and an error code is returned to the
caller.  When called from bnx2x_io_resume(), the return code is ignored
and the network interface is brought up unconditionally.  Later attempts
to send a packet via this interface result in a page fault due to a null
pointer reference.

This patch checks the return code of bnx2x_nic_load(), prints an error
message if necessary, and does not enable the interface.

Signed-off-by: David Christensen <[email-masked]>
Reviewed-by: Sridhar Samudrala <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
Signed-off-by: Sasha Levin <[email-masked]>
---
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
index 91ddde4d647c6..d21b22ed0b60a 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
@@ -14464,11 +14464,16 @@ static void bnx2x_io_resume(struct pci_dev *pdev)
 	bp->fw_seq = SHMEM_RD(bp, func_mb[BP_FW_MB_IDX(bp)].drv_mb_header) &
 							DRV_MSG_SEQ_NUMBER_MASK;
 
-	if (netif_running(dev))
-		bnx2x_nic_load(bp, LOAD_NORMAL);
+	if (netif_running(dev)) {
+		if (bnx2x_nic_load(bp, LOAD_NORMAL)) {
+			netdev_err(bp->dev, "Error during driver initialization, try unloading/reloading the driver\n");
+			goto done;
+		}
+	}
 
 	netif_device_attach(dev);
 
+done:
 	rtnl_unlock();
 }
 
-- 
2.40.1