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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5298DC433F5 for ; Mon, 2 May 2022 13:26:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354928AbiEBN3s (ORCPT ); Mon, 2 May 2022 09:29:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60024 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1385267AbiEBN3m (ORCPT ); Mon, 2 May 2022 09:29:42 -0400 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E3E8012AD8 for ; Mon, 2 May 2022 06:26:02 -0700 (PDT) Received: by mail-pj1-x102a.google.com with SMTP id r9so12668041pjo.5 for ; Mon, 02 May 2022 06:26:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=u1bDTYTZw1pMjI7Gqthg6fqrtoSnEG5Dk6/Cva86VCI=; b=J8Zdfqky2G1V8EPU1ecXE3UoyFHfxsLoaZAqG1MZpJBsvn3p/pzvopC7EtHDzygAzv WD3/uf9+OzfoKTnviGt0r3Wf9rA3sBjvr6JQ34+f2CZqLVAu3nCeEV6HQq0OXGPtBap+ WaZAaLCC0IXSkD0EcLYc7qX5h3MpjEoBY/Xd3bH4olmsTKKcEulfGRHQmB4ZfIhiYfqK SSPMfQv4pFCtmO17HeunMnDleLR/4yhC/Untzzc5EWObwKj3ToOw0qGR2Jf9jtXM7imX SW5LG9+WIexO9pvqe4S3Pp0Gr39wvgtlcSq4aFpbqOyk0Msg0XRXTREEnLeAhq7EoiF8 9w4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=u1bDTYTZw1pMjI7Gqthg6fqrtoSnEG5Dk6/Cva86VCI=; b=pKRHZdwiAkHVfSlNdyFFlXxNLwfaxm2w3g3VLUHp16CRPXJZCnsKLsuhI4PzSgE2Vh RrdT7LlpEbjj3KhhW1rkcRVNmH24PLkiEbBrG7QWX9IfWtJ/bylGLaBP7Mvftl2lH3QV mXLJ5+zqzsPxta5gaAX2owzhQiDQv1hr3AzhUEy+7FyIQsYifxOuHyylunlWV7vak60L SIRLBb82xYL0Eyfr2npC0cpUrg5ero+Gqjnx6+obQ7O3RutpWsROrlgL/Khd0CzGKCCw FLXTqZbY5b7iAdgIWuep2wc4i9KMhvYb2iG6BuXRnH6ooVmuYVlmL1WFiC2niZl1uIAG UbGw== X-Gm-Message-State: AOAM532PEFq3rz1cWUTcPTRgXQLM5sTa8TItLmpq/+q+F9OXX7sEO49a 5bFE8AXE09SWCegYdy+547+ZOg== X-Google-Smtp-Source: ABdhPJzQTiuO7lIQ/FePbEmWbZv+DY73/I4ctb8nms0SxtRXkj+EdjJSmDi2u1196zt5vr0VCWjOpA== X-Received: by 2002:a17:90b:3b4c:b0:1da:2001:a222 with SMTP id ot12-20020a17090b3b4c00b001da2001a222mr13020897pjb.84.1651497962364; Mon, 02 May 2022 06:26:02 -0700 (PDT) Received: from [192.168.4.166] (cpe-72-132-29-68.dc.res.rr.com. [72.132.29.68]) by smtp.gmail.com with ESMTPSA id m10-20020a170902db0a00b0015e8d4eb2dbsm4627740plx.293.2022.05.02.06.26.01 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 02 May 2022 06:26:01 -0700 (PDT) Message-ID: <6ad38ecc-b2a9-f0e9-f7c7-f312a2763f97@kernel.dk> Date: Mon, 2 May 2022 07:26:00 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [REGRESSION] lxc-stop hang on 5.17.x kernels Content-Language: en-US To: Daniel Harding , Pavel Begunkov Cc: regressions@lists.linux.dev, io-uring@vger.kernel.org, linux-kernel@vger.kernel.org References: <7925e262-e0d4-6791-e43b-d37e9d693414@living180.net> From: Jens Axboe In-Reply-To: <7925e262-e0d4-6791-e43b-d37e9d693414@living180.net> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 5/2/22 7:17 AM, Daniel Harding wrote: > I use lxc-4.0.12 on Gentoo, built with io-uring support > (--enable-liburing), targeting liburing-2.1. My kernel config is a > very lightly modified version of Fedora's generic kernel config. After > moving from the 5.16.x series to the 5.17.x kernel series, I started > noticed frequent hangs in lxc-stop. It doesn't happen 100% of the > time, but definitely more than 50% of the time. Bisecting narrowed > down the issue to commit aa43477b040251f451db0d844073ac00a8ab66ee: > io_uring: poll rework. Testing indicates the problem is still present > in 5.18-rc5. Unfortunately I do not have the expertise with the > codebases of either lxc or io-uring to try to debug the problem > further on my own, but I can easily apply patches to any of the > involved components (lxc, liburing, kernel) and rebuild for testing or > validation. I am also happy to provide any further information that > would be helpful with reproducing or debugging the problem. Do you have a recipe to reproduce the hang? That would make it significantly easier to figure out. -- Jens Axboe