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=-10.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 2A155C07E95 for ; Wed, 7 Jul 2021 18:42:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0E14061C98 for ; Wed, 7 Jul 2021 18:42:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231614AbhGGSpJ (ORCPT ); Wed, 7 Jul 2021 14:45:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41338 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231482AbhGGSpJ (ORCPT ); Wed, 7 Jul 2021 14:45:09 -0400 Received: from mail-ej1-x62c.google.com (mail-ej1-x62c.google.com [IPv6:2a00:1450:4864:20::62c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EF12DC061574 for ; Wed, 7 Jul 2021 11:42:28 -0700 (PDT) Received: by mail-ej1-x62c.google.com with SMTP id ga42so4865766ejc.6 for ; Wed, 07 Jul 2021 11:42:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=famzah-net.20150623.gappssmtp.com; s=20150623; h=to:from:subject:message-id:date:user-agent:mime-version :content-transfer-encoding:content-language; bh=Ev4xLSy5HqW3W1Px7/oMFO+6V02IJLBRYDeDv5aAbpY=; b=Luz25RWXmjWPH9pu6L6FihGJbijG+aU0t78SN8YLyy4rBolPKXm97pNP4Ma20TbWdN 0gL9uz81Y2gXCayqVhejyG7d9udFHRmXU4QlsUNxUuzUK3iv7TJe50hGZYT/qwD2BF6W AehQtcWtSQFUyU2J2zuAIOw0djFwH5Cs+9VD4aUHvWJlcxrarTKGfGxXf+zKJwWFiT+e 1ovluYr0Euh2KMp3UyOMQgcWL5i/ZYt97BOkCHeD4FntnqX0EBXsTi8c5DOBpGAGbOVq U6IYeWOWPbpHccX9QpQg1xrsiIyxNMptVNVXsbWbusEMB1OjSxOX4iuOPiXgvmRhNy8H 9lQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:from:subject:message-id:date:user-agent :mime-version:content-transfer-encoding:content-language; bh=Ev4xLSy5HqW3W1Px7/oMFO+6V02IJLBRYDeDv5aAbpY=; b=KkYKbfXuV9e1/eXNkNTy5/YJrnm/xEovvHasdTHGGCqHybW0d3McdsfhLbKeAi2UNn HxdNVoXD9W2QK+FR2d89+B0+62fvWCxIP+i2/lG9nYgROshFftHsGORHsTP9qkAEhRPF A6oEc0IdBX3ou1wpgW+01kQVbBZOCKUbfi5F+ALEKNJ9rb6SwMoAghnMg1JFZomeO7Ia Wh0XZkePv6L9H+2UgvGEmeAWIy/GC+KzBeHFBx8zfCzBk7w1MpYk69QXRw1reIb/1oe8 Nz2SyiJ653h58tiakLCXgf4iqLIH/h64KxCiVNo+pwSDlc7flpj2ENl6gkiQIjvlNkW5 UdYg== X-Gm-Message-State: AOAM533bs4As2r1n47a4Jr/HSocczW7rFc89rJyt6yqZelaacH2BeIzo exU5glFbNLF7JEZ6cGK0UqGfni8rP50kpA== X-Google-Smtp-Source: ABdhPJyHcvRilpxYpPJl6OaeI+Bzq5U6dh8lRIs9KZ2MSXYi3+UTpb6AqmLZGbYKpn3qCdMUOp62WQ== X-Received: by 2002:a17:906:d8cf:: with SMTP id re15mr25995743ejb.410.1625683347277; Wed, 07 Jul 2021 11:42:27 -0700 (PDT) Received: from [213.145.98.224] (224.98.145.213.in-addr.arpa. [213.145.98.224]) by smtp.googlemail.com with ESMTPSA id x16sm4717882ejj.74.2021.07.07.11.42.26 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 07 Jul 2021 11:42:27 -0700 (PDT) To: linux-ext4@vger.kernel.org From: Ivan Zahariev Subject: jbd2: fix deadlock while checkpoint thread waits commit thread to finish (backport to 4.14) Message-ID: <3221ced0-e8f3-53da-3474-28367272f35d@famzah.net> Date: Wed, 7 Jul 2021 21:42:25 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Hello, We're running Linux kernel 4.14.x and our systems occasionally suffer a bug which is already fixed: https://github.com/torvalds/linux/commit/53cf978457325d8fb2cdecd7981b31a8229e446e This bugfix hasn't been ported to Linux kernels 4.14 or 4.19. The patch applies cleanly. The two files "fs/jbd2/checkpoint.c" and "fs/jbd2/journal.c" seem pretty identical in the affected sections compared to kernel 5.4 where we have this bugfix already applied. Is it on purpose that this bugfix hasn't been ported to 4.14? Is it safe that we backport it manually in our kernel 4.14 builds? Or is the "ext4" system in 4.14 and 5.4 fundamentally different and this would lead to data loss or other problems? Thank you. Best regards. --Ivan