[ 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 <[email protected]> Cc: James Smart <[email protected]> Cc: Bart Van Assche <[email protected]> Cc: [email protected], Cc: Martin K . Petersen <[email protected]>, Cc: Christoph Hellwig <[email protected]>, Cc: James E . J . Bottomley <[email protected]>, Reviewed-by: Bart Van Assche <[email protected]> Reviewed-by: Johannes Thumshirn <[email protected]> Reviewed-by: Hannes Reinecke <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Tested-by: James Smart <[email protected]> Signed-off-by: Ming Lei <[email protected]> Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- 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 0b14aebfd1a8..4e04c79aa2c2 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -339,7 +339,6 @@ 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); } else { diff --git a/block/blk-mq.c b/block/blk-mq.c index eac444804736..55139d2fca3e 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2294,6 +2294,8 @@ 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
