From: Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
To: Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
Cc: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
Glauber Costa <glommer-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org>,
KAMEZAWA Hiroyuki
<kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org>,
Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>,
LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org
Subject: [PATCH 03/12] Revert "memcg: avoid dangling reference count in creation failure."
Date: Mon, 8 Apr 2013 14:33:35 +0800 [thread overview]
Message-ID: <516264BF.2020009@huawei.com> (raw)
In-Reply-To: <5162648B.9070802-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
From: Michal Hocko <mhocko-AlSwsSmVLrQ@public.gmane.org>
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-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
Signed-off-by: Michal Hocko <mhocko-AlSwsSmVLrQ@public.gmane.org>
---
mm/memcontrol.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 2364f4e..44cec72 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6250,8 +6250,6 @@ 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;
}
--
1.8.0.2
next prev parent reply other threads:[~2013-04-08 6:33 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-08 6:32 [PATCH 0/12][V2] memcg: make memcg's life cycle the same as cgroup Li Zefan
[not found] ` <5162648B.9070802-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2013-04-08 6:33 ` [PATCH 01/12] memcg: take reference before releasing rcu_read_lock Li Zefan
2013-04-08 6:33 ` [PATCH 02/12] memcg: avoid accessing memcg after releasing reference Li Zefan
2013-04-08 6:33 ` Li Zefan [this message]
2013-04-09 2:50 ` [PATCH 03/12] Revert "memcg: avoid dangling reference count in creation failure." Kamezawa Hiroyuki
2013-04-08 6:33 ` [PATCH 04/12] memcg, kmem: fix reference count handling on the error path Li Zefan
[not found] ` <516264D6.3090100-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2013-04-09 2:51 ` Kamezawa Hiroyuki
2013-04-08 6:35 ` [PATCH 09/12] cgroup: make sure parent won't be destroyed before its children Li Zefan
[not found] ` <51626516.3000603-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2013-04-08 15:36 ` Tejun Heo
2013-04-08 6:35 ` [PATCH 10/12] memcg: don't need to get a reference to the parent Li Zefan
2013-04-08 6:36 ` [PATCH 12/12] memcg: don't need to free memcg via RCU or workqueue Li Zefan
2013-04-08 14:15 ` Michal Hocko
[not found] ` <51626570.8000400-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2013-04-09 2:57 ` Kamezawa Hiroyuki
2013-04-08 6:34 ` [PATCH 05/12] memcg: use css_get() in sock_update_memcg() Li Zefan
2013-04-08 6:34 ` [PATCH 06/12] memcg: don't use mem_cgroup_get() when creating a kmemcg cache Li Zefan
2013-04-09 2:53 ` Kamezawa Hiroyuki
2013-04-08 6:34 ` [PATCH 07/12] memcg: use css_get/put when charging/uncharging kmem Li Zefan
2013-04-08 14:14 ` Michal Hocko
2013-04-09 2:55 ` Kamezawa Hiroyuki
2013-04-08 6:34 ` [PATCH 08/12] memcg: use css_get/put for swap memcg Li Zefan
2013-04-08 6:36 ` [PATCH 11/12] memcg: kill memcg refcnt Li Zefan
2013-04-08 6:36 ` [PATCH 13/12] memcg: don't need memcg->memcg_name Li Zefan
2013-04-08 14:25 ` Michal Hocko
[not found] ` <20130408142503.GH17178-2MMpYkNvuYDjFM9bn6wA6Q@public.gmane.org>
2013-04-09 1:28 ` Li Zefan
2013-04-09 3:10 ` Kamezawa Hiroyuki
[not found] ` <5163868B.3020905-+CUm20s59erQFUHtdCDX3A@public.gmane.org>
2013-04-09 3:18 ` Li Zefan
2013-04-09 3:46 ` Kamezawa Hiroyuki
[not found] ` <51638F2B.3000800-+CUm20s59erQFUHtdCDX3A@public.gmane.org>
2013-04-09 7:55 ` Glauber Costa
[not found] ` <5163887D.1040809-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
2013-04-09 3:59 ` Tejun Heo
2013-04-09 7:53 ` Glauber Costa
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=516264BF.2020009@huawei.com \
--to=lizefan-hv44wf8li93qt0dzr+alfa@public.gmane.org \
--cc=akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org \
--cc=cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=glommer-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org \
--cc=hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org \
--cc=kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org \
--cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org \
--cc=tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).