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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 52CB5C02194 for ; Thu, 6 Feb 2025 20:33:00 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D31E1280020; Thu, 6 Feb 2025 15:32:59 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id CDD64280004; Thu, 6 Feb 2025 15:32:59 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B5761280020; Thu, 6 Feb 2025 15:32:59 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 8C9F8280004 for ; Thu, 6 Feb 2025 15:32:59 -0500 (EST) Received: from smtpin29.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 16AB580E83 for ; Thu, 6 Feb 2025 20:32:59 +0000 (UTC) X-FDA: 83090668878.29.A13D450 Received: from mout.gmx.net (mout.gmx.net [212.227.17.20]) by imf21.hostedemail.com (Postfix) with ESMTP id 959BD1C003D for ; Thu, 6 Feb 2025 20:32:51 +0000 (UTC) Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=gmx.com header.s=s31663417 header.b=cqoeUZtX; dmarc=pass (policy=quarantine) header.from=gmx.com; spf=pass (imf21.hostedemail.com: domain of quwenruo.btrfs@gmx.com designates 212.227.17.20 as permitted sender) smtp.mailfrom=quwenruo.btrfs@gmx.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1738873972; a=rsa-sha256; cv=none; b=LHX/obJCD69l0Y4deQVRX/9tqj57GiubK30x9/Z/1FZiGRxaSoz8Lqln4NnXL+e2GNMdVe 9VQzt9IJ9CvkIL7UmcSwV2wD/CyOG8T15r7lXF2/p130gsYVw1tR+i3QHk6LHqju9p95EV /ljKKdZXrgh19oDbge9IRHwo1GABDBg= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=pass header.d=gmx.com header.s=s31663417 header.b=cqoeUZtX; dmarc=pass (policy=quarantine) header.from=gmx.com; spf=pass (imf21.hostedemail.com: domain of quwenruo.btrfs@gmx.com designates 212.227.17.20 as permitted sender) smtp.mailfrom=quwenruo.btrfs@gmx.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1738873971; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=9R+2vquaROtNZYSPIBsKoJzoSsjO0LkDiuYj8vkxDSk=; b=U/W4Jj0OwwsRlapT6ewD+fFKxD4YWkiwGbYJAW3RFPQjVjyJ3C7MerILio/wCu13Ktpgz+ wREqWXz0eqx8j07ZZ0/4ygzIMSpkh9KsORFbWptxp8oLNNrNBxuW0wMvqHEScgos/jMkqy mbIPeFEic8GVBoo5oXnifZzn2MPTYV4= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmx.com; s=s31663417; t=1738873964; x=1739478764; i=quwenruo.btrfs@gmx.com; bh=9R+2vquaROtNZYSPIBsKoJzoSsjO0LkDiuYj8vkxDSk=; h=X-UI-Sender-Class:Message-ID:Date:MIME-Version:Subject:To:Cc: References:From:In-Reply-To:Content-Type: Content-Transfer-Encoding:cc:content-transfer-encoding: content-type:date:from:message-id:mime-version:reply-to:subject: to; b=cqoeUZtXVpxRRmmPEFKsm7Vq8LoLsMZOl+AxSQGsUgFyIpdlq7jQzb8dBqeZ+LJW 2rsbAEnH16aX7R5oZAL/mH5qYF97U0W/rrkFIhnL42M5Pv+IPxUObFCq3no7i6BqL Rnr93Eh3Qlf4u1ScK0a2bB/nly/T2iK+71v/ifAFrwdx5MmZ3kbsZKgXCCzjcd4+l NvGwQyIeQ3Syei29l9836sFUnrtIfd8dV/iwF8VzTf9YPI8zHn0Mvc1ozE4Jhr73G fhgETjenruwUL+GSKg124Tm4VMhAsZPQO9uzTA7QrtgfXUE4wUAnD29n3eNLPHiIR DZGYJCMj8IHeKIrWYg== X-UI-Sender-Class: 724b4f7f-cbec-4199-ad4e-598c01a50d3a Received: from [172.16.0.191] ([159.196.52.54]) by mail.gmx.net (mrgmx105 [212.227.17.174]) with ESMTPSA (Nemesis) id 1MzhjF-1tSqxm2IyH-00zywp; Thu, 06 Feb 2025 21:32:44 +0100 Message-ID: Date: Fri, 7 Feb 2025 07:02:38 +1030 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] btrfs: always fallback to buffered write if the inode requires checksum To: "hch@infradead.org" , Qu Wenruo Cc: linux-btrfs@vger.kernel.org, Jan Kara , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org References: Content-Language: en-US From: Qu Wenruo Autocrypt: addr=quwenruo.btrfs@gmx.com; keydata= xsBNBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAHNIlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT7CwJQEEwEIAD4CGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCZxF1YAUJEP5a sQAKCRDCPZHzoSX+qF+mB/9gXu9C3BV0omDZBDWevJHxpWpOwQ8DxZEbk9b9LcrQlWdhFhyn xi+l5lRziV9ZGyYXp7N35a9t7GQJndMCFUWYoEa+1NCuxDs6bslfrCaGEGG/+wd6oIPb85xo naxnQ+SQtYLUFbU77WkUPaaIU8hH2BAfn9ZSDX9lIxheQE8ZYGGmo4wYpnN7/hSXALD7+oun tZljjGNT1o+/B8WVZtw/YZuCuHgZeaFdhcV2jsz7+iGb+LsqzHuznrXqbyUQgQT9kn8ZYFNW 7tf+LNxXuwedzRag4fxtR+5GVvJ41Oh/eygp8VqiMAtnFYaSlb9sjia1Mh+m+OBFeuXjgGlG VvQFzsBNBFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcga CbPEwhLj1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj /IrRUUka68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fN GSsRb+pKEKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0 q1eW4Jrv0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEv ABEBAAHCwHwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCZxF1gQUJEP5a0gAK CRDCPZHzoSX+qHGpB/kB8A7M7KGL5qzat+jBRoLwB0Y3Zax0QWuANVdZM3eJDlKJKJ4HKzjo B2Pcn4JXL2apSan2uJftaMbNQbwotvabLXkE7cPpnppnBq7iovmBw++/d8zQjLQLWInQ5kNq Vmi36kmq8o5c0f97QVjMryHlmSlEZ2Wwc1kURAe4lsRG2dNeAd4CAqmTw0cMIrR6R/Dpt3ma +8oGXJOmwWuDFKNV4G2XLKcghqrtcRf2zAGNogg3KulCykHHripG3kPKsb7fYVcSQtlt5R6v HZStaZBzw4PcDiaAF3pPDBd+0fIKS6BlpeNRSFG94RYrt84Qw77JWDOAZsyNfEIEE0J6LSR/ In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:cRQTi1qJo2eAixYQuee6+vk0gajfHyEYgIXNP1vsdNHKU3ytq8a uuB9xsRxXiuELi3fSA5fzYKr7Hx6rM+5u4OJ94Wl93muZSrI9UA0A+iJwlIR0BXkuXBvGnM PZbrPlHx62X6f3DrWbj2j/yE3B6HlbEtWzfGoF3GPWbM3IfJDjVaOrvdj9bhTuW7Fp76Lm9 LonIg80uwC4+gVY29qojA== UI-OutboundReport: notjunk:1;M01:P0:bAPSaGPjSMM=;A40M8/XugEnMLhwIE8apqxS8O5N 3QBTqotDk/4kZeHFO5Wm5oBaxOIEjAlGHtKD0mP6XaGeOGE23SWTrUgvJf2MpAGMuTqcXtw/L 5FhwxZAVsr84W4BekxEfN8yITFXPVi/ZfdD13NvGdZsH1C1TmG8k02uwnFDvh4gab6cct0Fea 7WQagvc9G2IAjm5AA1kUgEb/p9vq/CVQpAB1jq4w4gZm1HqeRudllErZUMucdHIJHziM9etB/ rwfTZVQ4kqOXuc0lW5qnVhkIX9zbY5a+gdb9sUaB9at/fpVUt+BtLfgdoPz7qcKL7JZvdnf7N J/LjpMES3Am+2x/VVYGsyO67WeS5V6fdX4Iy97hv873jr1aYmHjMM/0pjVoFHyyyvMfJytVMp P7T1GeJpaFCJLfTqK04fjJLa1KBinvdLKX2G75qWK72aUc7f2VltyaqYxBhfi0lKvP9sQ6ElP NN0x5wtphx0MrB7poE9mMK1lkLerGZR78zEt8iO92SkzUiZG4uQWazuuQyntWAQl8pvhk4UOq 2nfIePDWsjxRfa4QpaBh9QHUA09Nx4pVRlCNyI3sSlNPw3EFazpmrV/17DmG9HvfTxt7rUKEd UlL620vp/g3FmZyuluyGomP5Zm6N6K3Qku+mwpsG7mW8t5DtjEbLQxtRQvtmLZ6nea+FwHfHJ lc1BSUrhYvq/khQokQyZ+YEfjkMoSZOLR9p7k0cW/DBGndkflKapZh4cpjjcH1eLzPcJeJjLR fTyTkNKlbTMWQ1Uluyb1CxbC1yT4Gs+HJ5tzhKlZJTBXbUUwteb2ehxWLCDb0G5z0J5Y53ZXe USfi/FGOHQajFX5iQa2H42vVD+yZhK07XWlv5duCLGGO3ZSOxanlVso3bkCNDDOzAEVnrjEo5 PKJEzXvsAVmc4dBiI9M4GHzGQFleRHy3MbRlu1nVVD/EF/VcMZmZTjRiO21uQ9IrwHgltCEt7 ZGe0i5syO+Qh1Q7J9VszAYgb5OOZg/bQmHNQSfLiiRGjSMaxfjqJZvGnwoxhqFA9Y7xko++9B 7eFySf6XXsOM0g1s22Z9PRwDntHe9oHRLULw44L5xqCDD/XOY4oaOHxu07ShIZ7xTtwLqfxMu x/kEC14LL3ePzLZeOjqDDAwjejk8ailB/BL5RClg9/oqo/8am9dAxxeppwmmmsCGtBGY/Addz EL60dmVazcyERelHgmdt/7zzZSaGThsxAbBrynlJY8XvlFLrJkH7XL7SMFAuJeWVi2CGVyVgj fwYUOZGr2HZl/rsPxXtmCbK9O19T9iIjFhqLv2PQpQwXE0Jq8PSKJ9gZN6Lid3r12HKXrMzpU Pm7G0VoJ9nB1ia/HFDDSW+6hPSk80qFxJvdxovdXVK8wmLXFRxMiq4Fvo4Jv3aD7LPYhZC9bC lLFUrg6jLFzO7n+d0NQz/tviVloArlFSni+8AbE3IBN4z1exj3mEwgjLwS X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 959BD1C003D X-Stat-Signature: ncp4m457pbfxayzxtmtbyhoybynbwqfu X-Rspam-User: X-HE-Tag: 1738873971-686283 X-HE-Meta: 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 sWfS12VV DyHuN/ed5SIyUbXTBXu7iew+Uk47UJ14YFq9tFuQFvWAVZLlFCkE05rQtXkw77k2q7ABmR7oPeiF4pfJrM8kUX58OgV7hA0WCLIX1FU8qyN+bTwandLrGhgt63cdyF1vIHWwLAqOCONU5TrKln2HCE+b5uSyGSvgkiBi/menAqVsa8+lX2MHQhxkKvsQvTOHzFEzM2Q+P9h+M+TexfnM2UU4XN5JyDHNMdSUSkAeepZkAacbbTs56T3ZByQ0ymUKGdWsEqfsgX/7ZaaYw4hXk8Qx3eisrVbRsws84LY7e3nnsQa+vqaFG3SUQohibH7qFM+ZdfZ3EAafyFOZR7G+CvYiAAMkAOMh0Eit+r/uzpNqCt6w/8G5AQM8i2NzkwxPcFFkQsccLd6fkhDljb4SbK1X2U9+AFPLpoekRHdVk7+wYnhXgHhYAAQL9+p7DzjSMR4/xa64mvLkcXMckvig+WIXL5U9NA5HFXiIh X-Bogosity: Ham, tests=bogofilter, spamicity=0.016696, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: =E5=9C=A8 2025/2/7 00:43, hch@infradead.org =E5=86=99=E9=81=93: > On Tue, Feb 04, 2025 at 02:00:23PM +1030, Qu Wenruo wrote: >> [BUG] >> It is a long known bug that VM image on btrfs can lead to data csum >> mismatch, if the qemu is using direct-io for the image (this is commonl= y >> known as cache mode none). >> >> [CAUSE] >> Inside the VM, if the fs is EXT4 or XFS, or even NTFS from Windows, the >> fs is allowed to dirty/modify the folio even the folio is under >> writeback (as long as the address space doesn't have AS_STABLE_WRITES >> flag inherited from the block device). > > Btw, can you add an xfstests that reproduces this by modifying pages > under direct I/O? That would be really helpful to verify the code when > we want to turn back on real direct I/O eventually when the VM is fixed > to prevent the modifications. Sure, although I'm afraid it will need to be a C program instead. Thanks, Qu