From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Subject: Re: [PATCH v4 6/6] memcg: avoid dangling reference count in creation failure. Date: Tue, 22 Jan 2013 15:00:58 +0100 Message-ID: <20130122140058.GF28525@dhcp22.suse.cz> References: <1358862461-18046-1-git-send-email-glommer@parallels.com> <1358862461-18046-7-git-send-email-glommer@parallels.com> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <1358862461-18046-7-git-send-email-glommer-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Glauber Costa Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, Tejun Heo , Johannes Weiner , kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org On Tue 22-01-13 17:47:41, Glauber Costa wrote: > When use_hierarchy is enabled, we acquire an extra reference count > in our parent during cgroup creation. We don't release it, though, > if any failure exist in the creation process. > > Signed-off-by: Glauber Costa > Reported-by: Michal Hocko Acked-by: Michal Hocko > --- > mm/memcontrol.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 357324c..72a008e 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -6166,6 +6166,8 @@ 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; > } > -- > 1.8.1 > -- Michal Hocko SUSE Labs