From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) by kanga.kvack.org (Postfix) with ESMTP id AAEF26B02AA for ; Wed, 25 Jul 2018 09:01:25 -0400 (EDT) Received: by mail-ed1-f69.google.com with SMTP id i26-v6so3094810edr.4 for ; Wed, 25 Jul 2018 06:01:25 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id w13-v6si4625348eds.45.2018.07.25.06.01.24 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 25 Jul 2018 06:01:24 -0700 (PDT) Date: Wed, 25 Jul 2018 15:01:23 +0200 From: Michal Hocko Subject: Re: cgroup-aware OOM killer, how to move forward Message-ID: <20180725130123.GM28386@dhcp22.suse.cz> References: <20180711223959.GA13981@castle.DHCP.thefacebook.com> <9ef76b45-d50f-7dc6-d224-683ab23efdb0@I-love.SAKURA.ne.jp> <20180725001001.GA30802@castle.DHCP.thefacebook.com> <33510f1b-e038-8266-6482-f8f8891e5514@i-love.sakura.ne.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <33510f1b-e038-8266-6482-f8f8891e5514@i-love.sakura.ne.jp> Sender: owner-linux-mm@kvack.org List-ID: To: Tetsuo Handa Cc: Roman Gushchin , akpm@linux-foundation.org, linux-mm@kvack.org, rientjes@google.com, hannes@cmpxchg.org, tj@kernel.org, gthelen@google.com On Wed 25-07-18 21:23:11, Tetsuo Handa wrote: > Michal, I think that I hit WQ OOM lockup caused by lack of guaranteed schedule_timeout_*() for WQ. > I think we should immediately send https://marc.info/?l=linux-mm&m=153062798103081 > (or both http://lkml.kernel.org/r/20180709074706.30635-1-mhocko@kernel.org and > https://marc.info/?l=linux-mm&m=152723708623015 ) to linux.git so that we can send > to stable kernels without waiting for "mm, oom: cgroup-aware OOM killer" patchset. Then do not pollute unrelated threads. Really! The patch to drop the sleep from the oom_lock is in mmotm tree already. I really do not see why you make it more important than it really is (ohhh it is the dubious CVE you have filed?). If you have hit a WQ OOM lockup beucase of a missing schedule_timeout then report it in a new email thread and we can discuss the proper way of handling it. Thanks! -- Michal Hocko SUSE Labs