[PATCH] dm: free io_barrier after blk_cleanup_queue call

From: Tahsin Erdogan
Date: Mon Oct 10 2016 - 08:41:48 EST


dm_old_request_fn() has paths that access md->io_barrier. The party
destroying io_barrier should ensure that no future execution
of dm_old_request_fn() is possible. Move destruction to below
blk_cleanup_queue() to ensure this.

Signed-off-by: Tahsin Erdogan <tahsin@xxxxxxxxxx>
---
drivers/md/dm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index be35258324c1..ec513ee864f2 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1423,8 +1423,6 @@ static void cleanup_mapped_device(struct mapped_device *md)
if (md->bs)
bioset_free(md->bs);

- cleanup_srcu_struct(&md->io_barrier);
-
if (md->disk) {
spin_lock(&_minor_lock);
md->disk->private_data = NULL;
@@ -1436,6 +1434,8 @@ static void cleanup_mapped_device(struct mapped_device *md)
if (md->queue)
blk_cleanup_queue(md->queue);

+ cleanup_srcu_struct(&md->io_barrier);
+
if (md->bdev) {
bdput(md->bdev);
md->bdev = NULL;
--
2.8.0.rc3.226.g39d4020