[PATCH AUTOSEL 5.10 18/23] nvme-fc: avoid race between time out and tear down

From: Sasha Levin
Date: Tue Sep 28 2021 - 02:00:46 EST


From: James Smart <jsmart2021@xxxxxxxxx>

[ Upstream commit e5445dae29d25d7b03e0a10d3d4277a1d0c8119b ]

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@xxxxxxxxx>
Tested-by: Daniel Wagner <dwagner@xxxxxxx>
Reviewed-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
Reviewed-by: Daniel Wagner <dwagner@xxxxxxx>
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/nvme/host/fc.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
index 86c6862e71a1..906cab35afe7 100644
--- a/drivers/nvme/host/fc.c
+++ b/drivers/nvme/host/fc.c
@@ -2486,6 +2486,7 @@ __nvme_fc_abort_outstanding_ios(struct nvme_fc_ctrl *ctrl, bool start_queues)
*/
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);
@@ -2509,6 +2510,7 @@ __nvme_fc_abort_outstanding_ios(struct nvme_fc_ctrl *ctrl, bool start_queues)
* 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);
--
2.33.0