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 79280C433F5 for ; Wed, 13 Apr 2022 23:23:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235176AbiDMXZ4 (ORCPT ); Wed, 13 Apr 2022 19:25:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233812AbiDMXZz (ORCPT ); Wed, 13 Apr 2022 19:25:55 -0400 Received: from mout.gmx.net (mout.gmx.net [212.227.17.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 34D7725283; Wed, 13 Apr 2022 16:23:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1649892207; bh=UOmsfiUHZxEuNiv0Pgb/nZvDVXfQQUfQzVhysVasWek=; h=X-UI-Sender-Class:Date:Subject:To:References:From:In-Reply-To; b=Q/I88eJFE4/UE7peYUs6NcPHUPYa4V6tztoWnqsiWUEVczNTkIH8QDYC5urL+3RT1 I5I0OPenL58yKR5w35rOsE5TrNgROzFyyqpLN8KBeiXENJYz+QVm5Sw+L1ewpLpeO+ iy3ez3ElOvN7BXCGDMrZqs/IpqLQ3oxy0ss8X4NY= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([149.28.201.231]) by mail.gmx.net (mrgmx105 [212.227.17.174]) with ESMTPSA (Nemesis) id 1M9Fjb-1nYRD747TL-006KX6; Thu, 14 Apr 2022 01:23:27 +0200 Message-ID: <9b8f45cb-060b-0b32-ff60-b0861eca2a33@gmx.com> Date: Thu, 14 Apr 2022 07:23:23 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.8.0 Subject: Re: [PATCH v2 1/3] btrfs: avoid double clean up when submit_one_bio() failed Content-Language: en-US To: dsterba@suse.cz, Qu Wenruo , linux-btrfs@vger.kernel.org, stable@vger.kernel.org References: <0b13dccbc4d6e066530587d6c00c54b10c3d00d7.1649766550.git.wqu@suse.com> <20220412204104.GA15609@twin.jikos.cz> <447a2d76-dfff-9efb-09e8-9778ac4a44f2@gmx.com> <20220413134630.GI15609@twin.jikos.cz> From: Qu Wenruo In-Reply-To: <20220413134630.GI15609@twin.jikos.cz> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:xCSAXaW5SaudQTKuX8ob6JbdLDbOqjDpE6+Eij9silkcHUb7NJi dHo/RmOlzlckRWRfCdEd0k6avRIlF0zNAGY48xXpTO0f7WE8J2fiv3NO66/ek8GwyfD09w+ S6vOaZGcae3yVrLBzL88SpGS2tQ+tuqBBoFFSuDAapd7Oyszb/tO1hXrmKhatHjfnoRV9LH sspbg3ZryaeePAeO9cNWw== X-UI-Out-Filterresults: notjunk:1;V03:K0:JpfwP2CLRGc=:RFwyeGo8A2qTPQ9kQLKRS/ mT6PWStYgq3W3r0/05AQi4EW/LBWtPerxK1TJ18G6kQo3qGBY262oZap2P9kwMTbGmeWDnu4Y sJ6MZWNg663erC1Lf+391o6Kp0vSDAel7y9vINZMgiGMiL4alJgqh6xe1LFO+hpMAlrFZuCDx Yzo0vZy1NdhAuGFVxHnvsPfBrTB2JW8MQdS1HPQNlwprLYhN5MVtbJIOT02oImH3WaSzB6SFH 3+PmsoRfMEGcehLh7l2irBbTMQ1edB5codTRvA9YMUPM7y7vvZ1Ed6hl3n2Cdr+WMGZGJ+T5w OmOWiSoOYMMjghu635DDg5Lvf5Q3cc0kU/1fZ7kLx1uxRd976qCuSTk/9A60bcmyoeIowurMD JWbBWMOn9xFEeuRnthMPCZC6ix0DlCF4fc1jdDx2TlCBj/JsXgmDqTZChwStxeM4+K1TFJI8G kH86ZcAyN0GqTY7IOrmt87tQ5vP3MH670gjXYDuE3Xs+rXf6JKoQPxN0AXsR62e6XToFmQ6xa b46FDDMMLhAEJ8sw4eFvcxxNKJUqRGriR60UqOV2DDSaKX5HJ57mvu+P5wFC68I5Nj149w4fD z/0RaHeC+Pja7joi/dCtyBUfsH5cvYD1VQdw8VdZ/zPs0coroQHM+mfQMVnhocgE4A5I2gV9d gg+DGboxxmgf1UGh661OSkkTeQPpbIK2I2JJ6PclAXngETZ0aI1huZUkrCS3b1i5kpnF17r0D maH5KdmRW/NxHKd36ONC1wdrXMfUButrsRacHHQ8kXnHUsJdCjWKkLQNTqxrHIw84dvyUNSZ8 AKWWuDNIrNkMicRfYnhSd1lWXb2vRuIAii2sZe5QEXVKW0EK51sUeP8zWPfM63LWIJ0E+6D1m 9+AVHXxubABESv2YCWALMgp/TZBb3R0pl32eiXfr7x7+zSIFwOuggvGIV0Oh6rmp+qneMzwNn UVHXkvXsN0giNCieu6tpmiS/yTykUBEP+FggG8JB6Av1Q96VIY6f6uql7H2Hyvg46cJtsCz7a gas4plOaYQpJulmIHf11+b75y2KB7iR1XjlPSXHAQuOmQkEwly36K6I83lq20nyMLCgkjtdIi 8mE7kjPqk8PBKg= Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 2022/4/13 21:46, David Sterba wrote: > On Wed, Apr 13, 2022 at 07:32:41AM +0800, Qu Wenruo wrote: >> On 2022/4/13 04:41, David Sterba wrote: >>> On Tue, Apr 12, 2022 at 08:30:13PM +0800, Qu Wenruo wrote: >>>> The commit 1784b7d502a9 ("btrfs: handle csum lookup errors properly o= n >>>> reads") itself is completely fine, it's our existing code not properl= y >>>> handling the error from bio submission hook properly. >>>> >>>> This patch will make submit_one_bio() to return void so that the call= ers >>>> will never be able to do cleanup when bio submission hook fails. >>>> >>>> CC: stable@vger.kernel.org # 5.18+ >>> >>> BTW stable tags are only for released kernels, if it's still in some r= c >>> then Fixes: is appropriate. >> >> The problem is I don't have a good idea on which commit to be fixed. >> >> Commit 1784b7d502a9 ("btrfs: handle csum lookup errors properly on >> reads") is completely fine by itself. >> >> The problem is there for a long long time, but can only be triggered >> with IO errors with that newer commit. >> >> Should we really use that commit? It looks like a scapegoat to me... > > I see, so it does not make sense to put Fixes: if it's not clearly > caused by the patch, the text description of the problem and references > to patches that could affect is OK. > > Still the stable tag should reflect where the fix applies but 5.18 > hasn't been released so either it's a typo or you know roughly which > stable kernels should get the fix (5.15, 5.10, etc). Then I guess we can drop the stable tag. Before that mentioned commit, btrfs_lookup_bio_csum() will never return error, thus submit_one_bio() will not really fail (due to IO error). Although the error path is there for a long long time, we don't have easy way to trigger the problem. Thanks, Qu