[PATCH 4.18 216/235] scsi: lpfc: Fix panic if driver unloaded when port is offline

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: James Smart <jsmart2021@xxxxxxxxx>

[ Upstream commit d580c6137476ab307a66e278cf7dbc666230f714 ]

System crashes when the lpfc module is unloaded after making the port
offline

The nvme queue pointers were freed during port offline, but were later
accessed in pci remove path.

Validate the pointers in pci remove path before accessing them.

Signed-off-by: Dick Kennedy <dick.kennedy@xxxxxxxxxxxx>
Signed-off-by: James Smart <james.smart@xxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/scsi/lpfc/lpfc_nvme.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/scsi/lpfc/lpfc_nvme.c
+++ b/drivers/scsi/lpfc/lpfc_nvme.c
@@ -2976,7 +2976,7 @@ lpfc_nvme_wait_for_io_drain(struct lpfc_
 	struct lpfc_sli_ring  *pring;
 	u32 i, wait_cnt = 0;
 
-	if (phba->sli_rev < LPFC_SLI_REV4)
+	if (phba->sli_rev < LPFC_SLI_REV4 || !phba->sli4_hba.nvme_wq)
 		return;
 
 	/* Cycle through all NVME rings and make sure all outstanding
@@ -2985,6 +2985,9 @@ lpfc_nvme_wait_for_io_drain(struct lpfc_
 	for (i = 0; i < phba->cfg_nvme_io_channel; i++) {
 		pring = phba->sli4_hba.nvme_wq[i]->pring;
 
+		if (!pring)
+			continue;
+
 		/* Retrieve everything on the txcmplq */
 		while (!list_empty(&pring->txcmplq)) {
 			msleep(LPFC_XRI_EXCH_BUSY_WAIT_T1);