[PATCH 1/2] Revert "memcg: avoid dangling reference count in creation failure."

Michal Hocko
2013-04-03T08:53:53Z

This reverts commit e4715f01be697a3730c78f8ffffb595591d6a88c

mem_cgroup_put is hierarchy aware so mem_cgroup_put(memcg) already drops
an additional reference from all parents so the additional
mem_cgrroup_put(parent) potentially causes use-after-free.

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
---
mm/memcontrol.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index f608546..6de6d70 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6424,8 +6424,6 @@ mem_cgroup_css_online(struct cgroup *cont)
* call __mem_cgroup_free, so return directly
*/
mem_cgroup_put(memcg);
- if (parent->use_hierarchy)
- mem_cgroup_put(parent);
}
return error;
}
--
1.7.10.4