Patch "dm thin: fix race condition when destroying thin pool workqueue" has been added to the 3.14-stable tree

This is a note to let you know that I've just added the patch titled

dm thin: fix race condition when destroying thin pool workqueue

to the 3.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
dm-thin-fix-race-condition-when-destroying-thin-pool-workqueue.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Nikolay Borisov <[email protected]>
Date: Thu, 17 Dec 2015 18:03:35 +0200
Subject: dm thin: fix race condition when destroying thin pool workqueue

From: Nikolay Borisov <[email protected]>

commit 18d03e8c25f173f4107a40d0b8c24defb6ed69f3 upstream.

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.

---
 drivers/md/dm-thin.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -2568,8 +2568,8 @@ static void pool_postsuspend(struct dm_t
 	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);
 }

Patches currently in stable-queue which might be from [email protected] are

queue-3.14/dm-thin-fix-race-condition-when-destroying-thin-pool-workqueue.patch