Commit 95febeb6 authored by Jens Axboe's avatar Jens Axboe
Browse files

block: fix missing queue put in error path 

If we fail the submission queue checks, we don't put the queue afterwards.
This can cause various issues like stalls on scheduler switch or failure
to remove the device, or like in the original bug report, timeout waiting
for the device on reboot/restart.

While in there, fix a few whitespace discrepancies in the surrounding
code.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=215039


Fixes: b637108a ("blk-mq: fix filesystem I/O request allocation")
Reported-and-tested-by: default avatarStephen Smith <stephenmsmith@blueyonder.co.uk>
Reviewed-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 94c4b4fd

block/blk-mq.c

+8 −8
Original line number Diff line number Diff line
@@ -2543,8 +2543,7 @@ static struct request *blk_mq_get_new_requests(struct request_queue *q, 
	return NULL;

}



static inline bool blk_mq_can_use_cached_rq(struct request *rq,

		struct bio *bio)

static inline bool blk_mq_can_use_cached_rq(struct request *rq, struct bio *bio)

{

	if (blk_mq_get_hctx_type(bio->bi_opf) != rq->mq_hctx->type)

		return false;
@@ -2565,7 +2564,6 @@ static inline struct request *blk_mq_get_request(struct request_queue *q, 
	bool checked = false;



	if (plug) {



		rq = rq_list_peek(&plug->cached_rq);

		if (rq && rq->q == q) {

			if (unlikely(!submit_bio_checks(bio)))
@@ -2587,12 +2585,14 @@ static inline struct request *blk_mq_get_request(struct request_queue *q, 
fallback:

	if (unlikely(bio_queue_enter(bio)))

		return NULL;

	if (!checked && !submit_bio_checks(bio))

		return NULL;

	if (unlikely(!checked && !submit_bio_checks(bio)))

		goto out_put;

	rq = blk_mq_get_new_requests(q, plug, bio, nsegs, same_queue_rq);

	if (!rq)

		blk_queue_exit(q);

	if (rq)

		return rq;

out_put:

	blk_queue_exit(q);

	return NULL;

}



/**