3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Corey Wright <undefi...@pobox.com>

[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 <undefi...@pobox.com>
Fixes: e1db66a5fdcc ("dm: fix AB-BA deadlock in __dm_destroy()")
Cc: Sasha Levin <sas...@kernel.org>
---
 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);


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