Date: Wed, 6 Sep 2017 13:33:45 +0100
From: Roman Gushchin <guro@fb.com>
To: Michal Hocko <mhocko@kernel.org>
CC: <linux-mm@kvack.org>, Vladimir Davydov <vdavydov.dev@gmail.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>,
        David Rientjes <rientjes@google.com>,
        Andrew Morton <akpm@linux-foundation.org>, Tejun Heo <tj@kernel.org>,
        <kernel-team@fb.com>, <cgroups@vger.kernel.org>,
        <linux-doc@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [v7 2/5] mm, oom: cgroup-aware OOM killer
Message-ID: <20170906123345.GA12904@castle>
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On Wed, Sep 06, 2017 at 10:34:13AM +0200, Michal Hocko wrote:
> On Tue 05-09-17 21:23:57, Roman Gushchin wrote:
> > On Tue, Sep 05, 2017 at 04:57:00PM +0200, Michal Hocko wrote:
> [...]
> > > > @@ -810,6 +810,9 @@ static void __oom_kill_process(struct task_struct *victim)
> > > >  	struct mm_struct *mm;
> > > >  	bool can_oom_reap = true;
> > > >  
> > > > +	if (is_global_init(victim) || (victim->flags & PF_KTHREAD))
> > > > +		return;
> > > > +
> > > 
> > > This will leak a reference to the victim AFACS
> > 
> > Good catch!
> > I didn't fix this after moving reference dropping into __oom_kill_process().
> > Fixed.
> 
> Btw. didn't you want to check
> victim->signal->oom_score_adj == OOM_SCORE_ADJ_MIN
> 
> here as well? Maybe I've missed something but you still can kill a task
> which is oom disabled which I thought we agreed is the wrong thing to
> do.

Added. Thanks!