ublk_drv: update comment for __ublk_fail_req()

Since __ublk_rq_task_work always fails requests immediately during
exiting, __ublk_fail_req() is only called from abort context during
exiting. So lock is unnecessary.

Signed-off-by: ZiyangZhang <[email protected]>
Reviewed-by: Ming Lei <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

Author: old-memories

drivers/block/ublk_drv.c

@@ -605,8 +605,9 @@ static void ublk_complete_rq(struct request *req)
 }
 
 /*
- * __ublk_fail_req() may be called from abort context or ->ubq_daemon
- * context during exiting, so lock is required.
+ * Since __ublk_rq_task_work always fails requests immediately during
+ * exiting, __ublk_fail_req() is only called from abort context during
+ * exiting. So lock is unnecessary.
  *
  * Also aborting may not be started yet, keep in mind that one failed
  * request may be issued by block layer again.