From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , Sasha Levin , Corey Wright Subject: [PATCH 3.18 53/90] dm: remove duplicate dm_get_live_table() in __dm_destroy() Date: Mon, 19 Nov 2018 17:29:35 +0100 Message-Id: <20181119162629.402065358@linuxfoundation.org> In-Reply-To: <20181119162620.585061184@linuxfoundation.org> References: <20181119162620.585061184@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Corey Wright [3.18.y only, to fix a previous patch] __dm_destroy() takes io_barrier SRCU lock (dm_get_live_table) twice which leads to a deadlock. Remove taking lock before holding suspend_lock to prevent a different potential deadlock. Signed-off-by: Corey Wright Fixes: e1db66a5fdcc ("dm: fix AB-BA deadlock in __dm_destroy()") Cc: Sasha Levin --- drivers/md/dm.c | 1 - 1 file changed, 1 deletion(-) --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -2589,7 +2589,6 @@ static void __dm_destroy(struct mapped_d might_sleep(); spin_lock(&_minor_lock); - map = dm_get_live_table(md, &srcu_idx); idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md)))); set_bit(DMF_FREEING, &md->flags); spin_unlock(&_minor_lock);