[PATCH AUTOSEL 4.18 73/92] scsi: lpfc: Fix panic if driver unloaded when port is offline

From: Sasha Levin
Date: Fri Sep 14 2018 - 21:46:51 EST


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>
---
drivers/scsi/lpfc/lpfc_nvme.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/lpfc/lpfc_nvme.c b/drivers/scsi/lpfc/lpfc_nvme.c
index 76a5a99605aa..ada5a2aaee82 100644
--- a/drivers/scsi/lpfc/lpfc_nvme.c
+++ b/drivers/scsi/lpfc/lpfc_nvme.c
@@ -2970,7 +2970,7 @@ lpfc_nvme_wait_for_io_drain(struct lpfc_hba *phba)
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
@@ -2979,6 +2979,9 @@ lpfc_nvme_wait_for_io_drain(struct lpfc_hba *phba)
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);
--
2.17.1