From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nikolay Borisov , Mike Snitzer Subject: [PATCH 3.10 09/80] dm thin: fix race condition when destroying thin pool workqueue Date: Tue, 1 Mar 2016 15:45:03 -0800 Message-Id: <20160301234349.958485061@linuxfoundation.org> In-Reply-To: <20160301234349.667990420@linuxfoundation.org> References: <20160301234349.667990420@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nikolay Borisov 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. Fixes: 905e51b39a555 ("dm thin: commit outstanding data every second") Fixes: 85ad643b7e7e5 ("dm thin: add timeout to stop out-of-data-space mode holding IO forever") Signed-off-by: Nikolay Borisov Signed-off-by: Mike Snitzer Signed-off-by: Greg Kroah-Hartman --- drivers/md/dm-thin.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -2281,7 +2281,7 @@ 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_sync(&pool->waker); flush_workqueue(pool->wq); (void) commit_or_fallback(pool); }