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Date: Tue, 9 Jun 2009 00:21:28 +0900
Message-ID: <28c262360906080821v542bc573r496209402779d5c2@mail.gmail.com>
Subject: Re: [patch -mmotm] oom: only oom kill exiting tasks with attached 
	memory
From: Minchan Kim <minchan.kim@gmail.com>
To: David Rientjes <rientjes@google.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       Rik van Riel <riel@redhat.com>, linux-kernel@vger.kernel.org
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Hi, David.

On Mon, Jun 8, 2009 at 8:18 AM, David Rientjes<rientjes@google.com> wrote:
> On Sun, 7 Jun 2009, Balbir Singh wrote:
>
>> Seems like a good change to make. Did you encounter this situation on
>> a real machine?
>>
>
> I did, as the result of the chosen task remaining in PF_EXITING state with
> a detached mm following a previous oom kill.
> --

Let me have a question.
If I understand your situation properly, you mean

Time order
t1 < t2 < t3 < t4.

t1 : oom kill A process - send signal. it doesn't destroy mm_struct yet.
t2 : destroy A's mm_struct but it is in task list.
t3 : It happens OOM, again. Process A is selected again since it still
remain in task list
t4 : Now A's mm_struct is destroyed => situation you said.

Is right ?
Do you turn on sysctl oom_kill_allocating_task ?

-- 
Kinds regards,
Minchan Kim