4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ming Lei <ming.lei@xxxxxxxxxx> commit 105976f517791aed3b11f8f53b308a2069d42055 upstream. __blk_mq_requeue_request() covers two cases: - one is that the requeued request is added to hctx->dispatch, such as blk_mq_dispatch_rq_list() - another case is that the request is requeued to io scheduler, such as blk_mq_requeue_request(). We should call io sched's .requeue_request callback only for the 2nd case. Cc: Paolo Valente <paolo.valente@xxxxxxxxxx> Cc: Omar Sandoval <osandov@xxxxxx> Fixes: bd166ef183c2 ("blk-mq-sched: add framework for MQ capable IO schedulers") Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Bart Van Assche <bart.vanassche@xxxxxxx> Acked-by: Paolo Valente <paolo.valente@xxxxxxxxxx> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- block/blk-mq.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -638,7 +638,6 @@ static void __blk_mq_requeue_request(str trace_block_rq_requeue(q, rq); wbt_requeue(q->rq_wb, &rq->issue_stat); - blk_mq_sched_requeue_request(rq); if (test_and_clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags)) { if (q->dma_drain_size && blk_rq_bytes(rq)) @@ -650,6 +649,9 @@ void blk_mq_requeue_request(struct reque { __blk_mq_requeue_request(rq); + /* this request will be re-inserted to io scheduler queue */ + blk_mq_sched_requeue_request(rq); + BUG_ON(blk_queued_rq(rq)); blk_mq_add_to_requeue_list(rq, true, kick_requeue_list); }