From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48ADCC3A5A9 for ; Mon, 4 May 2020 08:03:12 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1437F20746 for ; Mon, 4 May 2020 08:03:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1437F20746 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A50308E0006; Mon, 4 May 2020 04:03:11 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A01228E0003; Mon, 4 May 2020 04:03:11 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 8EE718E0006; Mon, 4 May 2020 04:03:11 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0058.hostedemail.com [216.40.44.58]) by kanga.kvack.org (Postfix) with ESMTP id 74CE48E0003 for ; Mon, 4 May 2020 04:03:11 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 2E20119449 for ; Mon, 4 May 2020 08:03:11 +0000 (UTC) X-FDA: 76778296182.07.flag64_38e33b6d8a923 X-HE-Tag: flag64_38e33b6d8a923 X-Filterd-Recvd-Size: 3788 Received: from mail-wr1-f67.google.com (mail-wr1-f67.google.com [209.85.221.67]) by imf24.hostedemail.com (Postfix) with ESMTP for ; Mon, 4 May 2020 08:03:10 +0000 (UTC) Received: by mail-wr1-f67.google.com with SMTP id y3so700549wrt.1 for ; Mon, 04 May 2020 01:03:10 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=/dle8w9T/9fZDXiBv7O2x4fp68bt2R/VvMXMsCmw1pE=; b=jFUlEPto9y9xcpds73NUUXztpIuLApDDnXykUkIG2vGOAkvS3f0wHKLb07YS196T2/ dksxUUhzHjA+/xbY3SWxFa+uA/0luoKMj+7T86c1DWiXanNlFKyb8vn/epG9F1xa8VH2 GG72LuwYEw+8xTQ5Ej2DCD1xVn041SPLcdQwe8zaHxYOMoFi3dUyeVr5/h0mxPf49+C/ ZXR0EO2ebAlzIF/hg+5cpWoD5BRHZNhGcpzeFZwXm0gBQvzw2H5WNy2JDgCBO+rzch3l nF0mv3yM5U2FG+UyFzE/5Inyv+0ENBNBhXrU4R47FyClksx3r/kWHwDLXQYuydpbjIb5 +6VQ== X-Gm-Message-State: AGi0PuZMq+xPITWKLMXR18UlQ/H0I3i9UwsYfhNBh4/PydFMS5Gjb5MY cAq/912y/6cl5Z449kOXWt+O5bn4 X-Google-Smtp-Source: APiQypLfZaQESks6MYn/H7NmDLU6oeSUQW3/ziKVk3jh4HhIx6Ky1zIML5CFi2gReyWlooECxA5PkA== X-Received: by 2002:adf:9564:: with SMTP id 91mr18305719wrs.246.1588579389756; Mon, 04 May 2020 01:03:09 -0700 (PDT) Received: from localhost (ip-37-188-183-9.eurotel.cz. [37.188.183.9]) by smtp.gmail.com with ESMTPSA id d143sm12147653wmd.16.2020.05.04.01.03.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 04 May 2020 01:03:09 -0700 (PDT) Date: Mon, 4 May 2020 10:03:08 +0200 From: Michal Hocko To: Yafang Shao Cc: Shakeel Butt , Johannes Weiner , Roman Gushchin , Greg Thelen , Andrew Morton , Linux MM , Cgroups , LKML Subject: Re: [PATCH] memcg: oom: ignore oom warnings from memory.max Message-ID: <20200504080308.GI22838@dhcp22.suse.cz> References: <20200430182712.237526-1-shakeelb@google.com> <20200504070301.GC22838@dhcp22.suse.cz> <20200504073549.GE22838@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon 04-05-20 15:40:18, Yafang Shao wrote: > On Mon, May 4, 2020 at 3:35 PM Michal Hocko wrote: > > > > On Mon 04-05-20 15:26:52, Yafang Shao wrote: [...] > > > As explianed above, no eligible task is different from no task. > > > If there are some candidates but no one is eligible, the system will panic. > > > While if there's no task, it is definitely no OOM, because that's an > > > improssible thing for the system. > > > > This is very much possible situation when all eligible tasks have been > > already killed but they didn't really help to resolve the oom situation > > - e.g. in kernel memory leak or unbounded shmem consumption etc... > > > > That's still an impossible thing, because many tasks are invisible to > the oom killer. > See oom_unkillable_task(). I do not follow, really. oom_unkillable_task only says that global init cannot be killed and that it doesn't make any sense to kill kernel threads as they do not own any mm normally. -- Michal Hocko SUSE Labs