dm thin: fix race condition when destroying thin pool workqueue

When a thin pool is being destroyed delayed work items are
cancelled using cancel_delayed_work(), which doesn't guarantee that on
return the delayed item isn't running.  This can cause the work item to
requeue itself on an already destroyed workqueue.  Fix this by using
cancel_delayed_work_sync() which guarantees that on return the work item
is not running anymore.

Fixes: 905e51b39a ("dm thin: commit outstanding data every second")
Fixes: 85ad643b7e ("dm thin: add timeout to stop out-of-data-space mode holding IO forever")
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
This commit is contained in:
Nikolay Borisov 2015-12-17 18:03:35 +02:00 committed by Mike Snitzer
parent 512167788a
commit 18d03e8c25

View file

@ -3453,8 +3453,8 @@ static void pool_postsuspend(struct dm_target *ti)
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
cancel_delayed_work(&pool->waker);
cancel_delayed_work(&pool->no_space_timeout);
cancel_delayed_work_sync(&pool->waker);
cancel_delayed_work_sync(&pool->no_space_timeout);
flush_workqueue(pool->wq);
(void) commit(pool);
}