linux-kernel - Re: [mmotm][BUGFIX][PATCH] memcg: fix softlimit css refcnt handling(yet another one)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Mon, 7 Sep 2009 10:21:37 +0530
From:	Balbir Singh <balbir@...ux.vnet.ibm.com>
To:	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
Cc:	nishimura@....nes.nec.co.jp,
	Daisuke Nishimura <d-nishimura@....biglobe.ne.jp>,
	Andrew Morton <akpm@...ux-foundation.org>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [mmotm][BUGFIX][PATCH] memcg: fix softlimit css refcnt
 handling(yet another one)

* KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com> [2009-09-07 09:49:12]:

> > From: Daisuke Nishimura <nishimura@....nes.nec.co.jp>
> > 
> > refcount of the "victim" should be decremented before exiting the loop.
> > 
> > Signed-off-by: Daisuke Nishimura <nishimura@....nes.nec.co.jp>
> Nice!
> 
> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
> 
> > ---
> >  mm/memcontrol.c |    8 ++++++--
> >  1 files changed, 6 insertions(+), 2 deletions(-)
> > 
> > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > index ac51294..011aba6 100644
> > --- a/mm/memcontrol.c
> > +++ b/mm/memcontrol.c
> > @@ -1133,8 +1133,10 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem,
> >  				 * anything, it might because there are
> >  				 * no reclaimable pages under this hierarchy
> >  				 */
> > -				if (!check_soft || !total)
> > +				if (!check_soft || !total) {
> > +					css_put(&victim->css);
> >  					break;
> > +				}
> >  				/*
> >  				 * We want to do more targetted reclaim.
> >  				 * excess >> 2 is not to excessive so as to
> > @@ -1142,8 +1144,10 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem,
> >  				 * coming back to reclaim from this cgroup
> >  				 */
> >  				if (total >= (excess >> 2) ||
> > -					(loop > MEM_CGROUP_MAX_RECLAIM_LOOPS))
> > +					(loop > MEM_CGROUP_MAX_RECLAIM_LOOPS)) {
> > +					css_put(&victim->css);
> >  					break;
> > +				}
> >  			}
> >  		}
> >  		if (!mem_cgroup_local_usage(&victim->stat)) {

Good catch! Sorry for the late response I've been away


Acked-by: Balbir Singh <balbir@...ux.vnet.ibm.com>
 

-- 
	Balbir
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/