[3.13.y-ckt stable] Patch "dm btree: silence lockdep lock inversion in dm_btree_del()" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    dm btree: silence lockdep lock inversion in dm_btree_del()

to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11-ckt25.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 3f6db46fb195cde312da70d230cf0e47cbfae929 Mon Sep 17 00:00:00 2001
From: Joe Thornber <ejt at redhat.com>
Date: Fri, 3 Jul 2015 14:51:32 +0100
Subject: dm btree: silence lockdep lock inversion in dm_btree_del()

commit 1c7518794a3647eb345d59ee52844e8a40405198 upstream.

Allocate memory using GFP_NOIO when deleting a btree.  dm_btree_del()
can be called via an ioctl and we don't want to recurse into the FS or
block layer.

Signed-off-by: Joe Thornber <ejt at redhat.com>
Signed-off-by: Mike Snitzer <snitzer at redhat.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/md/persistent-data/dm-btree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/md/persistent-data/dm-btree.c b/drivers/md/persistent-data/dm-btree.c
index 9701d29..8dad984 100644
--- a/drivers/md/persistent-data/dm-btree.c
+++ b/drivers/md/persistent-data/dm-btree.c
@@ -255,7 +255,7 @@ int dm_btree_del(struct dm_btree_info *info, dm_block_t root)
 	int r;
 	struct del_stack *s;

-	s = kmalloc(sizeof(*s), GFP_KERNEL);
+	s = kmalloc(sizeof(*s), GFP_NOIO);
 	if (!s)
 		return -ENOMEM;
 	s->info = info;
--
1.9.1