From: John Garry <john.garry@xxxxxxxxxx> [ Upstream commit 5fe56de799ad03e92d794c7936bf363922b571df ] If in blk_mq_dispatch_rq_list() we find no budget, then we break of the dispatch loop, but the request may keep the driver tag, evaulated in 'nxt' in the previous loop iteration. Fix by putting the driver tag for that request. Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx> Signed-off-by: John Garry <john.garry@xxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- block/blk-mq.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 37ff8dfb8ab9f..2c3a1b2e07537 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1205,8 +1205,10 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, rq = list_first_entry(list, struct request, queuelist); hctx = rq->mq_hctx; - if (!got_budget && !blk_mq_get_dispatch_budget(hctx)) + if (!got_budget && !blk_mq_get_dispatch_budget(hctx)) { + blk_mq_put_driver_tag(rq); break; + } if (!blk_mq_get_driver_tag(rq)) { /* -- 2.20.1