[PATCH 4/4] nvme: unquiesce io queues when removing namespaces

[Ming Lei]

Error recovery can be interrupted by controller removal, then the
controller is left as quiesced, and IO hang can be caused.

Fix the issue by unquiescing controller unconditionally when removing
namespaces.

Reported-by: Chunguang Xu <brookxu.cn at gmail.com>
Closes: https://lore.kernel.org/linux-nvme/cover.1685350577.git.chunguang.xu@shopee.com/
Signed-off-by: Ming Lei <ming.lei at redhat.com>
---
 drivers/nvme/host/core.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index ec7bd33b7e5f..6d58b30ea835 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -4648,6 +4648,12 @@ void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
 	/* unfreeze queues which may be frozen from error recovery */
 	nvme_unfreeze_force(ctrl);
 
+	/*
+	 * Unquiesce io queues so any pending IO won't hang, especially
+	 * those submitted from scan work
+	 */
+	nvme_unquiesce_io_queues(ctrl);
+
 	/* prevent racing with ns scanning */
 	flush_work(&ctrl->scan_work);
 
@@ -4657,10 +4663,8 @@ void nvme_remove_namespaces(struct nvme_ctrl *ctrl)
 	 * removing the namespaces' disks; fail all the queues now to avoid
 	 * potentially having to clean up the failed sync later.
 	 */
-	if (ctrl->state == NVME_CTRL_DEAD) {
+	if (ctrl->state == NVME_CTRL_DEAD)
 		nvme_mark_namespaces_dead(ctrl);
-		nvme_unquiesce_io_queues(ctrl);
-	}
 
 	/* this is a no-op when called from the controller reset handler */
 	nvme_change_ctrl_state(ctrl, NVME_CTRL_DELETING_NOIO);
-- 
2.40.1