From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f70.google.com (mail-oi0-f70.google.com [209.85.218.70]) by kanga.kvack.org (Postfix) with ESMTP id 8FA8E6B0253 for ; Wed, 11 Oct 2017 07:15:17 -0400 (EDT) Received: by mail-oi0-f70.google.com with SMTP id u130so1002694oib.21 for ; Wed, 11 Oct 2017 04:15:17 -0700 (PDT) Received: from www262.sakura.ne.jp (www262.sakura.ne.jp. [2001:e42:101:1:202:181:97:72]) by mx.google.com with ESMTPS id x4si5745884oti.73.2017.10.11.04.15.14 for (version=TLS1 cipher=AES128-SHA bits=128/128); Wed, 11 Oct 2017 04:15:14 -0700 (PDT) Subject: Re: [PATCH] mm,page_alloc: softlockup on warn_alloc on From: Tetsuo Handa References: <20170915095849.9927-1-yuwang668899@gmail.com> <20170915143732.GA8397@cmpxchg.org> <201709161312.CAJ73470.FSOHFMVJLFQOOt@I-love.SAKURA.ne.jp> In-Reply-To: <201709161312.CAJ73470.FSOHFMVJLFQOOt@I-love.SAKURA.ne.jp> Message-Id: <201710112014.CCJ78649.tOMFSHOFVLOJFQ@I-love.SAKURA.ne.jp> Date: Wed, 11 Oct 2017 20:14:56 +0900 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linux-mm@kvack.org List-ID: To: hannes@cmpxchg.org Cc: yuwang668899@gmail.com, mhocko@suse.com, linux-mm@kvack.org, chenggang.qcg@alibaba-inc.com, yuwang.yuwang@alibaba-inc.com, akpm@linux-foundation.org Tetsuo Handa wrote: > Johannes Weiner wrote: > > On Fri, Sep 15, 2017 at 05:58:49PM +0800, wang Yu wrote: > > > From: "yuwang.yuwang" > > > > > > I found a softlockup when running some stress testcase in 4.9.x, > > > but i think the mainline have the same problem. > > > > > > call trace: > > > [365724.502896] NMI watchdog: BUG: soft lockup - CPU#31 stuck for 22s! > > > [jbd2/sda3-8:1164] > > > > We've started seeing the same thing on 4.11. Tons and tons of > > allocation stall warnings followed by the soft lock-ups. > > Forgot to comment. Since you are able to reproduce the problem (aren't you?), > please try setting 1 to /proc/sys/kernel/softlockup_all_cpu_backtrace so that > we can know what other CPUs are doing. It does not need to patch kernels. > Johannes, were you able to reproduce the problem? I'd like to continue warn_alloc() serialization patch if you can confirm that uncontrolled flooding of allocation stall warning can lead to soft lockups. -- 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