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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 DDD70C43381 for ; Tue, 5 Mar 2019 15:28:03 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A5D2E20842 for ; Tue, 5 Mar 2019 15:28:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A5D2E20842 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=techsingularity.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 3B5908E0003; Tue, 5 Mar 2019 10:28:03 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 365168E0001; Tue, 5 Mar 2019 10:28:03 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 207AC8E0003; Tue, 5 Mar 2019 10:28:03 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) by kanga.kvack.org (Postfix) with ESMTP id B9E4A8E0001 for ; Tue, 5 Mar 2019 10:28:02 -0500 (EST) Received: by mail-ed1-f72.google.com with SMTP id o27so4666225edc.14 for ; Tue, 05 Mar 2019 07:28:02 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:date:from:to :cc:subject:message-id:references:mime-version:content-disposition :content-transfer-encoding:in-reply-to:user-agent; bh=rqZeCh5C9TkCBKtZLyPcIqLgKZP2743+t2M6aZrupTc=; b=AqqDFCx9LVvclK60a+xIXKTwycsE6x+V/oOXvDraL2+HlyF4iWEG2PB4qL3DEaQErf DQsCePE7TWakDIqMvFLKhakl3UtLR8ac5h4v95UL2n1TnzRRy/Mjmem2K2LbCWG6OAFp 9EtER8g5Ter1pA5AE6xK2ZETLDtSlEiVSyezx03867eTZf4+Pyzf+J50yam0U+/yE3j9 Fd6UGxcey02pSnZ6ev9TnWZYL9xxxKkmkUFSmGpVYqRsEepbPH2mfUZfBIyGXR25EN8G 1yfusInzBaGOaJCerXtBj9ODNIm6YwT5xMvwLhuLS0s7UuQuCiD1Dr5BeCzoRUOj6AD2 jmJg== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of mgorman@techsingularity.net designates 46.22.139.233 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net X-Gm-Message-State: APjAAAXu7hjoNSWKuE7Q2ZmZeZl6rKzIg3O1IomJXL+CcaVTCdJhxxPm LIw4wj57hYxrLnM0u8ECLKcU1QP/+7cvGZFbuFtYBv4ffdSkVA6VliTGxm2rkIttq+wAJFPsMnt ZC+ECtU7tnHR01ZsqgSAXx1gqOTL51HI7boiixFdOB3xR1klV/I2i/sdgX41yg3Cu6A== X-Received: by 2002:aa7:c1d6:: with SMTP id d22mr20444258edp.180.1551799682278; Tue, 05 Mar 2019 07:28:02 -0800 (PST) X-Google-Smtp-Source: APXvYqzAIXEzHJIqgkMBzZ1kzPcuBzw6xozsEDuJVLa6eWtw+J26Xc0teMlq3hOcfI6w9TEgLBYl X-Received: by 2002:aa7:c1d6:: with SMTP id d22mr20444214edp.180.1551799681350; Tue, 05 Mar 2019 07:28:01 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1551799681; cv=none; d=google.com; s=arc-20160816; b=CAFdUoROwgJ35MQ4BoE6fqO6ldXHEcb2UgzoBSSjfdkzC8yR+vj4Swx720AGBG486B vuFLI7yQtniFmMTWx3lYOBRBeVUcQU1c96/N8rpc3pBMspyJ++ipqPiH/7JGL5NhaRR4 poek+KIf6Xw0tAJTvOFw4cHQo6D/1Md1AGtrg6+r0b0m8QD7owesfaaepXiTWc8hJD4W Ngteg1VOyYfCcbLUS0dYzu5Tnw9BOZ8Bf7F3I9xke5lFmEsJf1cXwzpkexv/k3WIbksd 8OQ4orko2KiE+/WwsZs8kQGFTHWWNQ6AEzbsSTg02ZsJ9099/OfA2BGVfUnRRw+RHDxP zBiA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=user-agent:in-reply-to:content-transfer-encoding :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=rqZeCh5C9TkCBKtZLyPcIqLgKZP2743+t2M6aZrupTc=; b=UHyHgCLWyCe9GpRFoYEAaaf/KAf/mBeCFMTJYnakoyRisnFoAwaj6y9FePEeR4QLm/ cQx6loDNygwCm4OCQp0aP1ECZPyzvIZliPyEq5lElISpF8+fCnTjZ58GJcVowDeuceAe z0d6YUhxHq+re4ywBbQhmFM9ZSL4YnJMqsTpsxbZioTA/7GifNSP6FnVU7xScPz40W42 hm6MhFGns3I/15HcFrygR59/79/vuBxlUDmvFvKHjGjB9oUtIX1V69nLPHjp6WTFJ2Lt HxLcdxwVf2Fqsjidh7L+qE8dPg40gfcXHvmoqfBt7rqUQgW935bGb2lMotZjbdPGQ0j9 iFMA== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of mgorman@techsingularity.net designates 46.22.139.233 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net Received: from outbound-smtp16.blacknight.com (outbound-smtp16.blacknight.com. [46.22.139.233]) by mx.google.com with ESMTPS id p18si2882240ejx.292.2019.03.05.07.28.01 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 05 Mar 2019 07:28:01 -0800 (PST) Received-SPF: pass (google.com: domain of mgorman@techsingularity.net designates 46.22.139.233 as permitted sender) client-ip=46.22.139.233; Authentication-Results: mx.google.com; spf=pass (google.com: domain of mgorman@techsingularity.net designates 46.22.139.233 as permitted sender) smtp.mailfrom=mgorman@techsingularity.net Received: from mail.blacknight.com (pemlinmail02.blacknight.ie [81.17.254.11]) by outbound-smtp16.blacknight.com (Postfix) with ESMTPS id F1DBD1C2DD6 for ; Tue, 5 Mar 2019 15:28:00 +0000 (GMT) Received: (qmail 12450 invoked from network); 5 Mar 2019 15:28:00 -0000 Received: from unknown (HELO techsingularity.net) (mgorman@techsingularity.net@[37.228.225.79]) by 81.17.254.9 with ESMTPSA (AES256-SHA encrypted, authenticated); 5 Mar 2019 15:28:00 -0000 Date: Tue, 5 Mar 2019 15:27:59 +0000 From: Mel Gorman To: Qian Cai Cc: vbabka@suse.cz, Linux-MM Subject: Re: low-memory crash with patch "capture a page under direct compaction" Message-ID: <20190305152759.GI9565@techsingularity.net> References: <604a92ae-cbbb-7c34-f9aa-f7c08925bedf@lca.pw> <20190305144234.GH9565@techsingularity.net> <1551798804.7087.7.camel@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1551798804.7087.7.camel@lca.pw> User-Agent: Mutt/1.10.1 (2018-07-13) 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 Tue, Mar 05, 2019 at 10:13:24AM -0500, Qian Cai wrote: > On Tue, 2019-03-05 at 14:42 +0000, Mel Gorman wrote: > > On Mon, Mar 04, 2019 at 10:55:04PM -0500, Qian Cai wrote: > > > Reverted the patches below from linux-next seems fixed a crash while running > > > LTP > > > oom01. > > > > > > 915c005358c1 mm, compaction: Capture a page under direct compaction -fix > > > e492a5711b67 mm, compaction: capture a page under direct compaction > > > > > > Especially, just removed this chunk along seems fixed the problem. > > > > > > --- a/mm/compaction.c > > > +++ b/mm/compaction.c > > > @@ -2227,10 +2227,10 @@ compact_zone(struct compact_control *cc, struct > > > capture_control *capc) > > >                 } > > > > > >                 /* Stop if a page has been captured */ > > > -               if (capc && capc->page) { > > > -                       ret = COMPACT_SUCCESS; > > > -                       break; > > > -               } > > > > > > > It's hard to make sense of how this is connected to the bug. The > > out-of-bounds warning would have required page flags to be corrupted > > quite badly or maybe the use of an uninitialised page. How reproducible > > has this been for you? I just ran the test 100 times with UBSAN and page > > alloc debugging enabled and it completed correctly. > > > > I did manage to reproduce this every time by running oom01 within 3 tries on > this x86_64 server and was unable to reproduce on arm64 and ppc64le servers so > far. > Ok, so there is something specific about the machine or the kernel config that is at play. You're seeing slub issues, page state issues etc. Have you seen this on any other x86-based machine? Also please post your kernel config. Are you certain that removing the block from your first email avoids any issue triggering? -- Mel Gorman SUSE Labs