[PATCH 4.14 157/164] blk-mq: Avoid that request queue removal can trigger list corruption

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Bart Van Assche <bart.vanassche@xxxxxxx>


[ Upstream commit aba7afc5671c23beade64d10caf86e24a9105dab ]

Avoid that removal of a request queue sporadically triggers the
following warning:

list_del corruption. next->prev should be ffff8807d649b970, but was 6b6b6b6b6b6b6b6b
WARNING: CPU: 3 PID: 342 at lib/list_debug.c:56 __list_del_entry_valid+0x92/0xa0
Call Trace:
 process_one_work+0x11b/0x660
 worker_thread+0x3d/0x3b0
 kthread+0x129/0x140
 ret_from_fork+0x27/0x40

Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxxx>
Cc: Johannes Thumshirn <jthumshirn@xxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 block/blk-core.c |    1 +
 1 file changed, 1 insertion(+)

--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -339,6 +339,7 @@ void blk_sync_queue(struct request_queue
 		struct blk_mq_hw_ctx *hctx;
 		int i;
 
+		cancel_delayed_work_sync(&q->requeue_work);
 		queue_for_each_hw_ctx(q, hctx, i)
 			cancel_delayed_work_sync(&hctx->run_work);
 	} else {