[ Upstream commit fbc2a15e3433058582e5635aabe48a3011a644a8 ] With holding queue's kobject refcount, it is safe for driver to schedule requeue. However, blk_mq_kick_requeue_list() may be called after blk_sync_queue() is done because of concurrent requeue activities, then requeue work may not be completed when freeing queue, and kernel oops is triggered. So moving the cancel of requeue_work into blk_mq_release() for avoiding race between requeue and freeing queue. Cc: Dongli Zhang <dongli.zhang@xxxxxxxxxx> Cc: James Smart <james.smart@xxxxxxxxxxxx> Cc: Bart Van Assche <bart.vanassche@xxxxxxx> Cc: linux-scsi@xxxxxxxxxxxxxxx, Cc: Martin K . Petersen <martin.petersen@xxxxxxxxxx>, Cc: Christoph Hellwig <hch@xxxxxx>, Cc: James E . J . Bottomley <jejb@xxxxxxxxxxxxxxxxxx>, Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx> Reviewed-by: Johannes Thumshirn <jthumshirn@xxxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Tested-by: James Smart <james.smart@xxxxxxxxxxxx> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- block/blk-core.c | 1 - block/blk-mq.c | 2 ++ 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/block/blk-core.c b/block/blk-core.c index b375cfea024c..2dd94b3e9ece 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -237,7 +237,6 @@ void blk_sync_queue(struct request_queue *q) 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); } diff --git a/block/blk-mq.c b/block/blk-mq.c index 8a41cc5974fe..11efca3534ad 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2666,6 +2666,8 @@ void blk_mq_release(struct request_queue *q) struct blk_mq_hw_ctx *hctx; unsigned int i; + cancel_delayed_work_sync(&q->requeue_work); + /* hctx kobj stays in hctx */ queue_for_each_hw_ctx(q, hctx, i) { if (!hctx) -- 2.20.1