[PATCH] Add missing del_gendisk to error path

[Zdenek Kabelac <zkabelac@redhat.com>]

Add missing del_gendisk() to error path when creation of workqueue fails.
Otherwice there is a resource leak and following warning is shown:

WARNING: at fs/sysfs/dir.c:487 sysfs_add_one+0xc5/0x160()
sysfs: cannot create duplicate filename '/devices/virtual/block/dm-0'

Signed-off-by: Zdenek Kabelac <zkabelac@redhat.com>

---
 drivers/md/dm.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index b4845b1..bf5961d 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1819,6 +1819,7 @@ static struct mapped_device *alloc_dev(int minor)
 bad_bdev:
 	destroy_workqueue(md->wq);
 bad_thread:
+	del_gendisk(md->disk);
 	put_disk(md->disk);
 bad_disk:
 	blk_cleanup_queue(md->queue);