From: James Smart <jsmart2021@gmail.com>
Date: Tue, 14 Sep 2021 11:20:07 +0200
Subject: nvme-fc: avoid race between time out and tear down
Patch-mainline: v5.15-rc3
Git-commit: e5445dae29d25d7b03e0a10d3d4277a1d0c8119b
References: bsc#1185762

To avoid race between time out and tear down, in tear down process,
first we quiesce the queue, and then delete the timer and cancel
the time out work for the queue.

This patch merges the admin and io sync ops into the queue teardown logic
as shown in the RDMA patch 3017013dcc "nvme-rdma: avoid race between time
out and tear down". There is no teardown_lock in nvme-fc.

Signed-off-by: James Smart <jsmart2021@gmail.com>
Tested-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/nvme/host/fc.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -2153,6 +2153,7 @@ static void
 	 */
 	if (ctrl->ctrl.queue_count > 1) {
 		nvme_stop_queues(&ctrl->ctrl);
+		nvme_sync_io_queues(&ctrl->ctrl);
 		blk_mq_tagset_busy_iter(&ctrl->tag_set,
 				nvme_fc_terminate_exchange, &ctrl->ctrl);
 		blk_mq_tagset_wait_completed_request(&ctrl->tag_set);
@@ -2176,6 +2177,7 @@ static void
 	 * clean up the admin queue. Same thing as above.
 	 */
 	blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
+	blk_sync_queue(ctrl->ctrl.admin_q);
 	blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
 				nvme_fc_terminate_exchange, &ctrl->ctrl);
 	blk_mq_tagset_wait_completed_request(&ctrl->admin_tag_set);