It is required to hold the queue lock when calling blk_run_queue_async() to avoid that a race between blk_run_queue_async() and blk_cleanup_queue() is triggered.
Signed-off-by: Bart Van Assche <[email protected]> --- drivers/md/dm-rq.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-rq.c b/drivers/md/dm-rq.c index f9f37ad..7df7948 100644 --- a/drivers/md/dm-rq.c +++ b/drivers/md/dm-rq.c @@ -210,6 +210,9 @@ static void rq_end_stats(struct mapped_device *md, struct request *orig) */ static void rq_completed(struct mapped_device *md, int rw, bool run_queue) { + struct request_queue *q = md->queue; + unsigned long flags; + atomic_dec(&md->pending[rw]); /* nudge anyone waiting on suspend queue */ @@ -222,8 +225,11 @@ static void rq_completed(struct mapped_device *md, int rw, bool run_queue) * back into ->request_fn() could deadlock attempting to grab the * queue lock again. */ - if (!md->queue->mq_ops && run_queue) - blk_run_queue_async(md->queue); + if (!q->mq_ops && run_queue) { + spin_lock_irqsave(q->queue_lock, flags); + blk_run_queue_async(q); + spin_unlock_irqrestore(q->queue_lock, flags); + } /* * dm_put() must be at the end of this function. See the comment above -- 2.10.1 -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
