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=-5.5 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 C7CCCC433DF for ; Wed, 12 Aug 2020 00:29:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9346A206F2 for ; Wed, 12 Aug 2020 00:29:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="T+9XrQ+s" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726611AbgHLA33 (ORCPT ); Tue, 11 Aug 2020 20:29:29 -0400 Received: from mout.gmx.net ([212.227.17.22]:47761 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726221AbgHLA33 (ORCPT ); Tue, 11 Aug 2020 20:29:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1597192164; bh=oLS/QegZwUQ4oEJg5jfVm/qSDXpRpu0Ooev46+vt13o=; h=X-UI-Sender-Class:Subject:To:References:From:Date:In-Reply-To; b=T+9XrQ+sOqRT2UX+7LiqEM1NEwKCBzi0P4f4mn7ggsSgr+XeRE71/FG7LkBhe8A9Y xeEVURr9s0lgyuQqXMEf3xnlBcyfchHYc7of2ElMzPuc4/15k2ePiAYBXh6UBpmKFV rppT4PSrOEprclaeXElH+vi3aftWhYdQ/ijjK6Fk= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([45.77.180.217]) by mail.gmx.com (mrgmx105 [212.227.17.174]) with ESMTPSA (Nemesis) id 1MMGRK-1kNriX1rd8-00JHQM; Wed, 12 Aug 2020 02:29:24 +0200 Subject: Re: [PATCH v3 3/5] btrfs: Detect unbalanced tree with empty leaf before crashing btree operations To: Josef Bacik , Qu Wenruo , linux-btrfs@vger.kernel.org References: <20200809120919.85271-1-wqu@suse.com> <20200809120919.85271-4-wqu@suse.com> <8d21ba85-52a5-5419-dc16-ceece8b0c3a8@toxicpanda.com> From: Qu Wenruo Autocrypt: addr=quwenruo.btrfs@gmx.com; prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAVQEEwEIAD4CGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCWdWCnQUJCWYC bgAKCRDCPZHzoSX+qAR8B/94VAsSNygx1C6dhb1u1Wp1Jr/lfO7QIOK/nf1PF0VpYjTQ2au8 ihf/RApTna31sVjBx3jzlmpy+lDoPdXwbI3Czx1PwDbdhAAjdRbvBmwM6cUWyqD+zjVm4RTG rFTPi3E7828YJ71Vpda2qghOYdnC45xCcjmHh8FwReLzsV2A6FtXsvd87bq6Iw2axOHVUax2 FGSbardMsHrya1dC2jF2R6n0uxaIc1bWGweYsq0LXvLcvjWH+zDgzYCUB0cfb+6Ib/ipSCYp 3i8BevMsTs62MOBmKz7til6Zdz0kkqDdSNOq8LgWGLOwUTqBh71+lqN2XBpTDu1eLZaNbxSI ilaVuQENBFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcga CbPEwhLj1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj /IrRUUka68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fN GSsRb+pKEKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0 q1eW4Jrv0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEv ABEBAAGJATwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1rgUJCWpOfwAK CRDCPZHzoSX+qFcEB/95cs8cM1OQdE/GgOfCGxwgckMeWyzOR7bkAWW0lDVp2hpgJuxBW/gy fmtBnUaifnggx3EE3ev8HTysZU9q0h+TJwwJKGv6sUc8qcTGFDtavnnl+r6xDUY7A6GvXEsS oCEEynby72byGeSovfq/4AWGNPBG1L61Exl+gbqfvbECP3ziXnob009+z9I4qXodHSYINfAk ZkA523JGap12LndJeLk3gfWNZfXEWyGnuciRGbqESkhIRav8ootsCIops/SqXm0/k+Kcl4gG UO/iD/T5oagaDh0QtOd8RWSMwLxwn8uIhpH84Q4X1LadJ5NCgGa6xPP5qqRuiC+9gZqbq4Nj Message-ID: Date: Wed, 12 Aug 2020 08:29:18 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:iQbqi3hHaSPUsr7ektEmsdPZ9cdz6WhRpUYQJ48IPaVWlP9+W+9 W84tie+U3r5bK+A/dtj4dnHEf4euaDwxn8EAXlnOShQ8xNlHYmmXIe+7/236jxzwb4qa71A coq024R1jOYXE/yXtunyNMO57f5/rNkKoX6icKRIZ7tTcUDjGnuou0WKz9Hn948KD0MTw1Z niwx9lu3NoB7Lx7Cd6/bw== X-UI-Out-Filterresults: notjunk:1;V03:K0:viLeO/rbc3s=:yoewnjD+Y6CQi43ddrdV8H 8ET6bMaBuD87uoZ+7ZMJQIiJhIJlGSjUqFn3DavxrBwh4j95xtsqAejQS6HpoDHFQi5arjOVN 8dBvHtXV3+Rf/0uN/DBEw5Juseqxob4R/EiwY6klIDstq4D0n/CSDJ6N9Nul0TxA9tG1m53zB LuM+ggdUFU2lMiRGlr3cg94n2Jrny9PXCc5zIuc0HeI/QKZvo3o+RePwbO3lTtCaC8MR7LtR4 T1CdpKW5wSy2dhj+3uuDIQ2MGYBUmtDlhvfgqZNvMRzDKBMu1AGiL93ad4KUSDF96wnq5JGOt frWwkX7sTOBQeH6zmRybNeeGyA00JZaJHlY36fTBQiiyZYonhp/VHUgZNOh0sPoDI86Z2ly0g p4uwfgNtxdRtXGgKJoUb2LqbDgQVHSQyT5vjTJwT6c1PuLlUhsn0DZK3wohgqecBoZ62TxgBR bwbhRWFqgBtJr7pgazu3MNAPoLjLhWUlPPaO2Kh+WHDiRwa3W6cRc+QzmcbYwp1F10lmejA1L LYS4np+1cU7sSdsihmsHNW5cEgcI1+ops0NqkJnV2EikX0/dIkye/92dj3XkFaZEw5YqmznOa b4JxWv70y/xygv1WWJSaVhAkyKyXuTjZ9IKl7fQKHGcDQHwyydsc/W8L8eMnCugw77oxYCkGP 5wyGaunrRAGRMIwKsoyOL2cAtGWGFW+SeuzYNPJKFuQnUUFSYnygAfQwHTQk0JvoCeIHmhtMI df5iWQHdx5glvXBwPOCchny1txiTgwZFq1gbny/pw1a3C5YAJ6wAgKtog1VkXP/Kw+x48l6u8 oxc5NhQCQt8JOi5hEd5W2aY3DlHXA1S22xFm8l6rw+Q6734uoE+tqFq7k9YGeTgf6wYK2PsqE EK4ahAzYTY+VwkWeyzoh+kmJqse+hJRyhRPx5tAHsEc51+tTKuNQfsI/HGKFv6ORFcxd7kRLn 3UayWWDiYGd7MTJtTc6ZO2Ou+J+PduviVT8UoW8FOZYgoaAF2aXoWCid7nvv44jYdC/TPyZGA 7KSgiNRRGu+Pj0x+PI03mwlThfPSQPhjjcJUL0xwlPq911swuaDjcNuQZTM8hHXaJbGQ3Anh7 AaJINviVmS/iU+ImJ07q4r+zout2TzqOko2ao7nrES30WsPaA81mNKCudnc5vqp9FMm8RBULj KhoHCnuoIIGo4GKL9mKUoZNAZfTv8iGZ8KKo3BHF5CH8B214JjFv74uYFM8T4LZRCPlwagyqe pS+OjArPN8n3skppEcnd0W6s75PhaTgC+g2k2hA== Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 2020/8/12 =E4=B8=8A=E5=8D=888:23, Josef Bacik wrote: > On 8/11/20 7:04 PM, Qu Wenruo wrote: >> >> [...] >>> Which I assume is the problem?=C2=A0 The generation is 19, is that > >>> last_trans_committed?=C2=A0 Seems like this check just needs to be mov= ed >>> lower, right?=C2=A0 Thanks, >> >> Nope, that generation 19 is valid. That fs has a higher generation, so >> that's completely valid. >> >> The generation 19 is there because there is another csum leaf whose >> generation is 19. >> > > Then this patch does nothing, because we already have this check lower, > so how exactly did it make the panic go away?=C2=A0 Thanks, > > Josef Sorry, I don't get your point. The generation 19 isn't larger than last_trans_committed, so that check has nothing to do with this case. And then it goes to the header_nritems() check, which is 0, and with first_key present, which is invalid and we error out, rejecting the corrupted leaf. What's the problem then? Thanks, Qu