From: James Smart <jsmart2021@gmail.com>
Date: Sun, 22 Mar 2020 11:12:57 -0700
Subject: scsi: lpfc: Fix crash after handling a pci error
Patch-mainline: v5.7-rc1
Git-commit: 4cd70891308dfb875ef31060c4a4aa8872630a2e
References: bsc#1164777 bsc#1164780 bsc#1165211

Injecting EEH on a 32GB card is causing kernel oops

The pci error handler is doing an IO flush and the offline code is also
doing an IO flush. When the 1st flush is complete the hdwq is destroyed
(freed), yet the second flush accesses the hdwq and crashes.

Added a check in lpfc_sli4_fush_io_rings to check both the HBA_IOQ_FLUSH
flag and the hdwq pointer to see if it is already set and not already
freed.

Link: https://lore.kernel.org/r/20200322181304.37655-6-jsmart2021@gmail.com
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Daniel Wagner <dwagner@suse.de>
---
 drivers/scsi/lpfc/lpfc_sli.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -4046,6 +4046,11 @@ lpfc_sli_flush_io_rings(struct lpfc_hba
 	struct lpfc_iocbq *piocb, *next_iocb;
 
 	spin_lock_irq(&phba->hbalock);
+	if (phba->hba_flag & HBA_IOQ_FLUSH ||
+	    !phba->sli4_hba.hdwq) {
+		spin_unlock_irq(&phba->hbalock);
+		return;
+	}
 	/* Indicate the I/O queues are flushed */
 	phba->hba_flag |= HBA_IOQ_FLUSH;
 	spin_unlock_irq(&phba->hbalock);