[PATCH 4.9 53/68] scsi: fnic: do not queue commands during fwreset

Greg Kroah-Hartman
2020-02-03T16:27:33Z

From: Hannes Reinecke <hare@suse.de>

[ 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@suse.de
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 c056b8111ad27..7bf6102b4c3d5 100644
--- a/drivers/scsi/fnic/fnic_scsi.c
+++ b/drivers/scsi/fnic/fnic_scsi.c
@@ -445,6 +445,9 @@ 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));
ret = fc_remote_port_chkready(rport);
if (ret) {
--
2.20.1