dm rq: take request_queue lock while clearing QUEUE_FLAG_STOPPED

Every call of queue_flag_clear_unlocked() after block device
initialization has finished is wrong if blk_cleanup_queue() can be
called concurrently.  Convert queue_flag_clear_unlocked() into
queue_flag_clear() and protect it by the block layer queue lock.

Also, factor out dm_mq_start_queue().

Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
This commit is contained in:
Mike Snitzer 2016-09-01 11:59:33 -04:00
parent 2397a15aff
commit 9dbeaeabac
1 changed files with 14 additions and 5 deletions

View File

@ -73,15 +73,24 @@ static void dm_old_start_queue(struct request_queue *q)
spin_unlock_irqrestore(q->queue_lock, flags);
}
static void dm_mq_start_queue(struct request_queue *q)
{
unsigned long flags;
spin_lock_irqsave(q->queue_lock, flags);
queue_flag_clear(QUEUE_FLAG_STOPPED, q);
spin_unlock_irqrestore(q->queue_lock, flags);
blk_mq_start_stopped_hw_queues(q, true);
blk_mq_kick_requeue_list(q);
}
void dm_start_queue(struct request_queue *q)
{
if (!q->mq_ops)
dm_old_start_queue(q);
else {
queue_flag_clear_unlocked(QUEUE_FLAG_STOPPED, q);
blk_mq_start_stopped_hw_queues(q, true);
blk_mq_kick_requeue_list(q);
}
else
dm_mq_start_queue(q);
}
static void dm_old_stop_queue(struct request_queue *q)