[02/15] lpfc: Fix system crash when port is reset.

Commit Message

Guilherme G. Piccoli May 15, 2017, 7:31 p.m. UTC

Hi James and Dick, thanks for this patch. We were investigating a pretty
similar issue, and we raised a patch that looks like yours.
Since you sent this one, we reviewed and seems it's missing a hunk to
prevent the issue we are dealing here, in PCI error recovery.

Please see the attached patch. Basically, lpfc is dereferencing a NULL
pointer on PCI error recovery path in lpfc_els_flush_cmd(). Feel free to
take this hunk on your patch, or if you prefer we can send a complete patch.

Thanks in advance,


Guilherme

---
 drivers/scsi/lpfc/lpfc_els.c | 7 +++++++
 1 file changed, 7 insertions(+)

Patch

diff --git a/drivers/scsi/lpfc/lpfc_els.c b/drivers/scsi/lpfc/lpfc_els.c
index 67827e397431..4e354194cb54 100644
--- a/drivers/scsi/lpfc/lpfc_els.c
+++ b/drivers/scsi/lpfc/lpfc_els.c
@@ -7441,6 +7441,13 @@  lpfc_els_flush_cmd(struct lpfc_vport *vport)
 	 */
 	spin_lock_irq(&phba->hbalock);
 	pring = lpfc_phba_elsring(phba);
+
+	/* Bail out if we've no ELS wq, like in PCI error recovery case. */
+	if (unlikely(!pring)) {
+		spin_unlock_irq(&phba->hbalock);
+		return;
+	}
+
 	if (phba->sli_rev == LPFC_SLI_REV4)
 		spin_lock(&pring->ring_lock);