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=-5.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 18C86C2B9F4 for ; Thu, 17 Jun 2021 18:02:54 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D93D4613DD for ; Thu, 17 Jun 2021 18:02:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D93D4613DD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=eikelenboom.it Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.144116.265321 (Exim 4.92) (envelope-from ) id 1ltwLd-0001WP-Rn; Thu, 17 Jun 2021 18:02:37 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 144116.265321; Thu, 17 Jun 2021 18:02:37 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1ltwLd-0001WI-On; Thu, 17 Jun 2021 18:02:37 +0000 Received: by outflank-mailman (input) for mailman id 144116; Thu, 17 Jun 2021 18:02:36 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1ltwLc-0001WC-0y for xen-devel@lists.xenproject.org; Thu, 17 Jun 2021 18:02:36 +0000 Received: from server.eikelenboom.it (unknown [91.121.65.215]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 48daf945-e739-46c9-b34b-328a35bdbc7c; Thu, 17 Jun 2021 18:02:34 +0000 (UTC) Received: from 76-24-144-85.ftth.glasoperator.nl ([85.144.24.76]:51064 helo=[172.16.1.50]) by server.eikelenboom.it with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1ltwQB-0006fU-Be; Thu, 17 Jun 2021 20:07:19 +0200 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 48daf945-e739-46c9-b34b-328a35bdbc7c DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=eikelenboom.it; s=20180706; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=PiN3z2mKDdT5442Y+muKtJpynotCbE1hW/7caNM/RJk=; b=SFGTJae2VtNYejTAt/O1zGbbFs WqNBFGLdNgegQgVYtdoSjbl7L5z3kKUVETjdj8jFbq5hVa3nKtFGd0AZvB97rSgiBOzlYFHcPHVIL zua+3fLh2ng3XN3RDLyuLGzPskn7WR6QA31nbq3EZCvvyJkm1lihbSwwq4f6BxAa/Hyo=; Subject: Re: Linux 5.13-rc6 regression to 5.12.x: kernel OOM and panic during kernel boot in low memory Xen VM's (256MB assigned memory). To: Rasmus Villemoes , Linus Torvalds Cc: linux-kernel , "xen-devel@lists.xenproject.org" References: <9108c22e-3521-9e24-6124-7776d947b788@rasmusvillemoes.dk> From: Sander Eikelenboom Message-ID: <0b12f27b-1109-b621-c969-10814b2c1c2f@eikelenboom.it> Date: Thu, 17 Jun 2021 20:02:27 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <9108c22e-3521-9e24-6124-7776d947b788@rasmusvillemoes.dk> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit On 17/06/2021 17:37, Rasmus Villemoes wrote: > On 17/06/2021 17.01, Linus Torvalds wrote: >> On Thu, Jun 17, 2021 at 2:26 AM Sander Eikelenboom wrote: >>> >>> I just tried to upgrade and test the linux kernel going from the 5.12 kernel series to 5.13-rc6 on my homeserver with Xen, but ran in some trouble. >>> >>> Some VM's boot fine (with more than 256MB memory assigned), but the smaller (memory wise) PVH ones crash during kernel boot due to OOM. >>> Booting VM's with 5.12(.9) kernel still works fine, also when dom0 is running 5.13-rc6 (but it has more memory assigned, so that is not unexpected). >> >> Adding Rasmus to the cc, because this looks kind of like the async >> roofs population thing that caused some other oom issues too. > > Yes, that looks like the same issue. > >> Rasmus? Original report here: >> >> https://lore.kernel.org/lkml/ee8bf04c-6e55-1d9b-7bdb-25e6108e8e1e@eikelenboom.it/ >> >> I do find it odd that we'd be running out of memory so early.. > > Indeed. It would be nice to know if these also reproduce with > initramfs_async=0 on the command line. > > But what is even more curious is that in the other report > (https://lore.kernel.org/lkml/20210607144419.GA23706@xsang-OptiPlex-9020/), > it seemed to trigger with _more_ memory - though I may be misreading > what Oliver was telling me: > >> please be noted that we use 'vmalloc=512M' for both parent and this > commit. >> since it's ok on parent but oom on this commit, we want to send this > report >> to show the potential problem of the commit on some cases. >> >> we also tested by changing to use 'vmalloc=128M', it will succeed. > > Those tests were done in a VM with 16G memory, and then he also wrote > >> we also tried to follow exactly above steps to test on >> some local machine (8G memory), but cannot reproduce. > > Are there some special rules for what memory pools PID1 versus the > kworker threads can dip into? > > > Side note: I also had a ppc64 report with different symptoms (the > initramfs was corrupted), but that turned out to also reproduce with > e7cb072eb98 reverted, so that is likely unrelated. But just FTR that > thread is here: > https://lore.kernel.org/lkml/CA+QYu4qxf2CYe2gC6EYnOHXPKS-+cEXL=MnUvqRFaN7W1i6ahQ@mail.gmail.com/ > > Rasmus > I choose to first finish the bisection attempt, not so suprising it ends up with: e7cb072eb988e46295512617c39d004f9e1c26f8 is the first bad commit So at least that link is confirmed. I also checked out booting with "initramfs_async=0" and now the guest boots with the 5.13-rc6-ish kernel which fails without that. -- Sander