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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 304C7C3F2CE for ; Thu, 5 Mar 2020 00:46:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F09A72084E for ; Thu, 5 Mar 2020 00:46:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="EoLyx3NU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725875AbgCEAqZ (ORCPT ); Wed, 4 Mar 2020 19:46:25 -0500 Received: from mout.gmx.net ([212.227.17.20]:55307 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725852AbgCEAqY (ORCPT ); Wed, 4 Mar 2020 19:46:24 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1583369178; bh=yKBxtmSK7+/YS22cLugkfFcabl+sCb+4F1OZ5WVLaB4=; h=X-UI-Sender-Class:Subject:To:References:From:Date:In-Reply-To; b=EoLyx3NUyOIyz2hsZvtp7YN0XspYxWJtlrBQRgl/yhcfQCqY1aAoS3KKs/Wgo0qDY e+U/JtWwkui84kd/ReQo7TehlvuVd7wLMP1q7KKaEt5cAhmZRyd4t3FY8kKt4KWz7f 3CkoD/t/QOF6eESuq7e8mOxG1Mg5Z7IwyNST5Vp8= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([149.28.201.231]) by mail.gmx.com (mrgmx105 [212.227.17.174]) with ESMTPSA (Nemesis) id 1MhlKy-1jnPFR3Y8m-00dlNs; Thu, 05 Mar 2020 01:46:18 +0100 Subject: Re: [PATCH] btrfs-progs: Output proper csum string if csum mismatch To: dsterba@suse.cz, Qu Wenruo , linux-btrfs@vger.kernel.org References: <20200120093205.37824-1-wqu@suse.com> <20200304142802.GU2902@twin.jikos.cz> 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 AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAU4EEwEIADgCGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1oQAKCRDC PZHzoSX+qCY6CACd+mWu3okGwRKXju6bou+7VkqCaHTdyXwWFTsr+/0ly5nUdDtT3yEVggPJ 3VP70wjlrxUjNjFb6iIvGYxiPOrop1NGwGYvQktgRhaIhALG6rPoSSAhGNjwGVRw0km0PlIN D29BTj/lYEk+jVM1YL0QLgAE1AI3krihg/lp/fQT53wLhR8YZIF8ETXbClQG1vJ0cllPuEEv efKxRyiTSjB+PsozSvYWhXsPeJ+KKjFen7ebE5reQTPFzSHctCdPnoR/4jSPlnTlnEvLeqcD ZTuKfQe1gWrPeevQzgCtgBF/WjIOeJs41klnYzC3DymuQlmFubss0jShLOW8eSOOWhLRuQEN BFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcgaCbPEwhLj 1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj/IrRUUka 68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fNGSsRb+pK EKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0q1eW4Jrv 0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEvABEBAAGJ ATwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1rgUJCWpOfwAKCRDCPZHz oSX+qFcEB/95cs8cM1OQdE/GgOfCGxwgckMeWyzOR7bkAWW0lDVp2hpgJuxBW/gyfmtBnUai fnggx3EE3ev8HTysZU9q0h+TJwwJKGv6sUc8qcTGFDtavnnl+r6xDUY7A6GvXEsSoCEEynby 72byGeSovfq/4AWGNPBG1L61Exl+gbqfvbECP3ziXnob009+z9I4qXodHSYINfAkZkA523JG ap12LndJeLk3gfWNZfXEWyGnuciRGbqESkhIRav8ootsCIops/SqXm0/k+Kcl4gGUO/iD/T5 oagaDh0QtOd8RWSMwLxwn8uIhpH84Q4X1LadJ5NCgGa6xPP5qqRuiC+9gZqbq4Nj Message-ID: <5fe0776c-4e99-e124-4211-0abe9a90924d@gmx.com> Date: Thu, 5 Mar 2020 08:46:13 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20200304142802.GU2902@twin.jikos.cz> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="VMnVUQczo2bYebPDcXT1yyZXHgMydrMhc" X-Provags-ID: V03:K1:KzS6fFxbGq5wJV+S7QrXHk2vZP2hQxjfpqYDmKqL2szDsdVDt0k vi2T7jepPbqRZATm015yeZmyaLZVZgBR+d13CbCQxKjIfTJiCrEworgcN2u59HchzV2o4hn uY4+EOZEn+eU5S7uRnZDXss1PXjZc9BNoH3MohnkMiJEv/7XEYuqiRuP7Jo8vq/uv41k9l9 1+9rCxwFZue+bDc6hT8zQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:hbl3Bnx0M4w=:ZFaURh0dooG6PAAeObnmP5 rU4wX6B/Lb5hwhuSrX8Dlr1/9VdFpazFs0Qpf1IwmOwakXl/Zih/X578sPiFfLwMihVsoTJZM UoKloY6GUaLAptuzrtTHCatYlRPW+eUjFdw2Bdn1xqDquWayuFa0Me56yQhzsuWI7tvvTrdEW kzKGpLbA8htieTflsf6j2kvuLK7DLxIxeoRc5TrsDCCiiY6EinC21CabTyYlKPW3M/7A1akV+ /K8f5fPykaZTiMUILY72z2JgM0gBWxZwhAH1n2E94dlQROtifDFqQcGPC5+VczcDPwMw15rHX 9wH3LeKrho+aDmOBIierd/2LEeC5ZBc/nY4IvGhNSt48GOerV5jt3em3xRujqDIu+rcd0nlWy DN8WQj5NiMi2MOB1yApKlZ2UdVip5Q4ThZPW6NdMj1mFe3fR0GwNfXHl0T9MEcSWZ4zzKNhpJ pk2UTvT8aajxIHo6FV6qPUJsbczWl1NVaOtp32YnNh9hIP+S/R/p8hgDkjdHYxc33aMZk/BJw oCYvbdqr46ofMPmb28hPc6yA+0UooNY9GScfFPzex1WFRBT34kzGNzKY/EXFPmdXDLCLqu2AU bx4tI0DygUigAwkgh9mD9Dw6+2FPDp7KsC6Z4ERrE6D4az6maYSnuofig3UI3mAaa8PkxEg2G W4YB78JFJxhH3VQ98o5v1dvsqEw7A/XN8UoWSGzgKLoQh7BI4MznDJ+eYuRYjFWasORfwd+VJ 7Zfz4BS+KDvc/qLy/yWcylbJzjLmvpOqb1xfbocg/xE70BB5iG52WjQyhU0mWiQc+6Ey6XayE Y0SDCs4C02LC6k5LxWM5i+pWYpNL0m2uk1B5ml/2dP/eNJsN5XfUmjad4TcW1etpjbeSe8H7F dgeOwv6sFmDnJZ0Ilp35iLkFKDk7VWz1MGnxrItebZuZcUecRXRlkyc4JTfSoFaKUZHJ5NKg+ eRP7wWU2DzqGMCSHNl5MI+8VuAXbZa9spsL1YOHQ7Oty9zQuVV4yeWhiWJkBz8jl9lcstfr4/ CIyhE9UTGZgvTeJ5l9MoPc4SmoAwPeseBzBbhB6cwS3QNq4dkzU2PvOZvIhI/J8FLLSy7OKdu QnyjldWcTBogEDlubyKJfSytopD2UoA318NwG5ctoHzQo5xgILFiFcfVIZqCibpEak3fOyehJ +469OWfx4c5HuZIfek/0fQfTcUJysOfAOOjBetliv3vHlDW9ROJ+C0LXYOAxJz1RF1spCQyR5 u+njZ3EnCeT2BObeA Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --VMnVUQczo2bYebPDcXT1yyZXHgMydrMhc Content-Type: multipart/mixed; boundary="PE0p4FCF0eHQ5AUTXk8OckOUHfPlCMePW" --PE0p4FCF0eHQ5AUTXk8OckOUHfPlCMePW Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2020/3/4 =E4=B8=8B=E5=8D=8810:28, David Sterba wrote: > On Mon, Jan 20, 2020 at 05:32:05PM +0800, Qu Wenruo wrote: >> Introduce a new helper, csum_to_string(), to convert binary csum to >> string. >> >> And use it in check_extent_csums(), so that >> "btrfs check --check-data-csum" could report the following human >> readable output: >> mirror 1 bytenr 13631488 csum 0x13fec125 expected csum 0x98757625 >> >> Other than the original octane one: >> mirror 1 bytenr 13631488 csum 19 expected csum 152 >> >> It also has the extra handling for 32 bytes csum (e.g. SHA256). >> For such long csum, it needs 66 characters (+2 for "0x") to just outpu= t >> one hash, so this function would truncate them into the following >> format: >> 0xaabb...ccdd >> | \- The tailing 2 bytes >> \--------- The leading 2 bytes >=20 > Kernel prints the whole checksum and also 2 on one line, > btrfs_print_data_csum_error. The short version is ok for quick comparin= g > but for consistency do you think it's too bad to print the whole > checksum? Eg. when I see errors, copy&paste the checksum and can cross > check with the kernel messages/logs. >=20 Personally speaking, for kernel I'm in the middle land, leaning a little more towards shorter csum. But I'm not confident enough for kernel, thus there is no such patch for kernel submitted. For longer csum, unless we have some intentional conflicting algo, it's really hard to craft csum which makes the leading and tailing 8 bytes. Furthermore, the only csum human can really use is the csum for all 0 page. Otherwise all csum makes not much sense to human. But still, full csum may still make sense for certain corner case, and I don't want even a small chance that user reports csum matches in dmesg but still causing EIO. So I hesitate for kernel patch. As usual, you have the final say, and if kernel patch is needed I'm pretty happy to submit. Thanks, Qu --PE0p4FCF0eHQ5AUTXk8OckOUHfPlCMePW-- --VMnVUQczo2bYebPDcXT1yyZXHgMydrMhc Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAl5gS9YACgkQwj2R86El /qiaqQf/Vh+PDZYLpe/g9cvRxfnhRqMCrqRgFOjASkgJC4mEYhLCKuIee5oajS6t 4wu/FRWMs4wrc/YC9kpS0Y/wYa0t2iPK4Y6wZ0eCwSogbODwj9rJACF6Hb7Z+xis +sXV69DnMgbkOYpvF0ceWN0HH4l9Xu7Qko1OEwuC1xs/0j4G8AAXfTQcZhu4vpJn 50TmiQalpCCWD/atEBz7Mjev281gCuW5UJwZEp8Xohl6iGTH6YCxcrTvSDcDsUlT t2Z6ttPK0/aGikR+TKnyDA6UzrYdneCNnl/qKTf7BPSQ0kzUYRTv/KhYnxO8RelY ZcGtPaIs0VrExVwcOoMFP2iV9jRjgA== =JLEv -----END PGP SIGNATURE----- --VMnVUQczo2bYebPDcXT1yyZXHgMydrMhc--