[PATCH 5.4 71/90] scsi: fnic: do not queue commands during fwreset

From: Greg Kroah-Hartman
Date: Mon Feb 03 2020 - 11:40:21 EST


From: Hannes Reinecke <hare@xxxxxxx>

[ Upstream commit 0e2209629fec427ba75a6351486153a9feddd36b ]

When a link is going down the driver will be calling fnic_cleanup_io(),
which will traverse all commands and calling 'done' for each found command.
While the traversal is handled under the host_lock, calling 'done' happens
after the host_lock is being dropped.

As fnic_queuecommand_lck() is being called with the host_lock held, it
might well be that it will pick the command being selected for abortion
from the above routine and enqueue it for sending, but then 'done' is being
called on that very command from the above routine.

Which of course confuses the hell out of the scsi midlayer.

So fix this by not queueing commands when fnic_cleanup_io is active.

Link: https://lore.kernel.org/r/20200116102053.62755-1-hare@xxxxxxx
Signed-off-by: Hannes Reinecke <hare@xxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/scsi/fnic/fnic_scsi.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/scsi/fnic/fnic_scsi.c b/drivers/scsi/fnic/fnic_scsi.c
index 80608b53897bb..e3f5c91d5e4fe 100644
--- a/drivers/scsi/fnic/fnic_scsi.c
+++ b/drivers/scsi/fnic/fnic_scsi.c
@@ -439,6 +439,9 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_
if (unlikely(fnic_chk_state_flags_locked(fnic, FNIC_FLAGS_IO_BLOCKED)))
return SCSI_MLQUEUE_HOST_BUSY;

+ if (unlikely(fnic_chk_state_flags_locked(fnic, FNIC_FLAGS_FWRESET)))
+ return SCSI_MLQUEUE_HOST_BUSY;
+
rport = starget_to_rport(scsi_target(sc->device));
if (!rport) {
FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
--
2.20.1