From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751758AbdHGOxs (ORCPT ); Mon, 7 Aug 2017 10:53:48 -0400 Received: from mx2.suse.de ([195.135.220.15]:47826 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751364AbdHGOxr (ORCPT ); Mon, 7 Aug 2017 10:53:47 -0400 Date: Mon, 7 Aug 2017 16:21:21 +0200 From: Michal Hocko To: Andrew Morton Cc: David Rientjes , Johannes Weiner , Roman Gushchin , Tetsuo Handa , linux-mm@kvack.org, LKML Subject: Re: [PATCH 0/2] mm, oom: do not grant oom victims full memory reserves access Message-ID: <20170807142121.GK32434@dhcp22.suse.cz> References: <20170727090357.3205-1-mhocko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170727090357.3205-1-mhocko@kernel.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 27-07-17 11:03:55, Michal Hocko wrote: > Hi, > this is a part of a larger series I posted back in Oct last year [1]. I > have dropped patch 3 because it was incorrect and patch 4 is not > applicable without it. > > The primary reason to apply patch 1 is to remove a risk of the complete > memory depletion by oom victims. While this is a theoretical risk right > now there is a demand for memcg aware oom killer which might kill all > processes inside a memcg which can be a lot of tasks. That would make > the risk quite real. > > This issue is addressed by limiting access to memory reserves. We no > longer use TIF_MEMDIE to grant the access and use tsk_is_oom_victim > instead. See Patch 1 for more details. Patch 2 is a trivial follow up > cleanup. > > I would still like to get rid of TIF_MEMDIE completely but I do not have > time to do it now and it is not a pressing issue. > > [1] http://lkml.kernel.org/r/20161004090009.7974-1-mhocko@kernel.org Are there any more comments/questions? I will resubmit if not. -- Michal Hocko SUSE Labs