From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-f72.google.com (mail-lf0-f72.google.com [209.85.215.72]) by kanga.kvack.org (Postfix) with ESMTP id F09236B0253 for ; Thu, 7 Jul 2016 12:54:24 -0400 (EDT) Received: by mail-lf0-f72.google.com with SMTP id a2so14792593lfe.0 for ; Thu, 07 Jul 2016 09:54:24 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id 203si1797079wmk.116.2016.07.07.09.54.23 for (version=TLS1 cipher=AES128-SHA bits=128/128); Thu, 07 Jul 2016 09:54:23 -0700 (PDT) Date: Thu, 7 Jul 2016 18:54:21 +0200 From: Michal Hocko Subject: Re: [PATCH 6/8] mm,oom_reaper: Stop clearing TIF_MEMDIE on remote thread. Message-ID: <20160707165421.GP5379@dhcp22.suse.cz> References: <201607031135.AAH95347.MVOHQtFJFLOOFS@I-love.SAKURA.ne.jp> <201607031140.BDG64095.VJFOOLHSFMFtOQ@I-love.SAKURA.ne.jp> <20160707140604.GN5379@dhcp22.suse.cz> <201607080110.FHF78128.VOOLFOQFJFSHtM@I-love.SAKURA.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201607080110.FHF78128.VOOLFOQFJFSHtM@I-love.SAKURA.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: linux-mm@kvack.org, akpm@linux-foundation.org, oleg@redhat.com, rientjes@google.com, vdavydov@parallels.com, mst@redhat.com On Fri 08-07-16 01:10:02, Tetsuo Handa wrote: > Michal Hocko wrote: > > On Sun 03-07-16 11:40:41, Tetsuo Handa wrote: > > > >From 00b7a14653c9700429f89e4512f6000a39cce59d Mon Sep 17 00:00:00 2001 > > > From: Tetsuo Handa > > > Date: Sat, 2 Jul 2016 23:03:03 +0900 > > > Subject: [PATCH 6/8] mm,oom_reaper: Stop clearing TIF_MEMDIE on remote thread. > > > > > > Since oom_has_pending_mm() controls whether to select next OOM victim, > > > we no longer need to clear TIF_MEMDIE on remote thread. Therefore, > > > revert related changes in commit 36324a990cf578b5 ("oom: clear TIF_MEMDIE > > > after oom_reaper managed to unmap the address space") and > > > commit e26796066fdf929c ("oom: make oom_reaper freezable") and > > > commit 74070542099c66d8 ("oom, suspend: fix oom_reaper vs. > > > oom_killer_disable race"). > > > > The last revert is not safe. See > > http://lkml.kernel.org/r/1467365190-24640-3-git-send-email-mhocko@kernel.org > > Why? Because there is no guarantee of calling exit_oom_victim and thus oom_disable making a forward progress. The changelog referenced above tries to explain that. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org