From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f180.google.com (mail-pg1-f180.google.com [209.85.215.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 48689363 for ; Fri, 23 Jun 2023 01:06:10 +0000 (UTC) Received: by mail-pg1-f180.google.com with SMTP id 41be03b00d2f7-54f75f85a17so138779a12.0 for ; Thu, 22 Jun 2023 18:06:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1687482369; x=1690074369; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=FvhuIIVvKv0fuQ+6tTOIBoMGzj6AvWTNCnkT84dvlWk=; b=XErsvJ4DdWRzfegm18+ppDABJi95b1Qg2ElH45DtvpWdaxcbDFT6KND169FegrvhYg LpSD6sp7i9vzmpqSDgDgJKnWpc5Y1JdNqq7guQFw2zr3+v8SGXY2oO4fsRE5MpGHMzJA 4/xj6p5uibtWgepAI7WPEV+w61/XaSFxlWMhjAmtKcmTIdv+VTZxyNPW01h+XCFZ1VhL TCTLJM0Yhk6p6IkyQkbY1S3b7u4QRWPDl1cE4E6SYLPf5uuHIa2aLNjsg8M3/YkgGqf/ Q32FtJ9xBROtRxGrd7e0dVlPc6nLTcgbt4HXSfxyb9zeOKy1EuhFEJkGWiBxfDMPflwP mKEw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687482369; x=1690074369; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=FvhuIIVvKv0fuQ+6tTOIBoMGzj6AvWTNCnkT84dvlWk=; b=RweOhTxIkhjoRibsI02iyT3bFUHynZSkUje1ZIQU1vEGyWYzj6QsCY9Y7pb56lDF8E YS6f/p22z0AghvULXfB4XXeVEwiyLlrGNemCgJk2bJh8h2x/M/ylyYqV7e4qLElyVpmX Ee+9DrUooekGvbKanrQc4lm0XZsDk3h0Ne3w4SKXPptnIztgHE0XR9EjxRanlwtzfPJk fDHWfNV8bpJRM1+8WkzBtcFJUpNPc8oCcCYUY+wCOEI4LO9QljaJQ+fsba3SokfLv4Ky NgGnnhg05H7CXfy7Z2h7HEAmVckerT6j34IbF8eG62+FvB1daF+XINesf5r6W//hY8CR YmsQ== X-Gm-Message-State: AC+VfDzhZYxCY5FlZ0n1S4KVvazSRr8zWvvgHR79ra8hhSvlGN6z+x3I YtXOqmA2XlL+pv+qXUSd3Kg= X-Google-Smtp-Source: ACHHUZ6sj6zZAJmnu/bn+OZ7d9vsFPzQGo6z+Gj7R8ENWzV89+QgiLfebpcvgrTXmEQqTt7LCgOVEA== X-Received: by 2002:a05:6a20:7d8b:b0:122:6de4:125d with SMTP id v11-20020a056a207d8b00b001226de4125dmr10362491pzj.19.1687482369279; Thu, 22 Jun 2023 18:06:09 -0700 (PDT) Received: from debian.me ([103.131.18.64]) by smtp.gmail.com with ESMTPSA id bb5-20020a170902bc8500b001a0567811fbsm5576623plb.127.2023.06.22.18.06.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 22 Jun 2023 18:06:08 -0700 (PDT) Received: by debian.me (Postfix, from userid 1000) id 910E48B2EC0F; Fri, 23 Jun 2023 08:06:02 +0700 (WIB) Date: Fri, 23 Jun 2023 08:06:02 +0700 From: Bagas Sanjaya To: Sean Greenslade , linux-ext4@vger.kernel.org, Ye Bin , Theodore Ts'o , Thorsten Leemhuis Cc: Linux Kernel Mailing List , Linux Regressions Subject: Re: RO mount of ext4 filesystem causes writes Message-ID: References: Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="oHvmzLVb4TIpJ2OW" Content-Disposition: inline In-Reply-To: --oHvmzLVb4TIpJ2OW Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jun 12, 2023 at 01:20:47PM +0700, Bagas Sanjaya wrote: > On Sun, Jun 11, 2023 at 10:32:53PM -0700, Sean Greenslade wrote: > > Hello, folks. > >=20 > > I noticed a change in behavior of ext4 in recent kernels. I make use of > > several luks loopback images formatted as ext4 that I mount read-only > > most of the time. I use rsync to synchronize the backing images between > > machines. In the past, mouning the images as read-only would not touch > > the backing image contents at all, but recently this changed. Every > > mount, even ones that are RO from the start, will cause some small > > writes to the backing image and thus force rsync to scan the whole file. > >=20 > > I confirmed that the issue is still present on v6.4.rc6, so I performed > > a bisect and landed on the following commit: > >=20 > > > eee00237fa5ec8f704f7323b54e48cc34e2d9168 is the first bad commit > > > commit eee00237fa5ec8f704f7323b54e48cc34e2d9168 > > > Author: Ye Bin > > > Date: Tue Mar 7 14:17:02 2023 +0800 > > >=20 > > > ext4: commit super block if fs record error when journal record w= ithout error > >=20 > > That certainly looks like a likely cause of my issue, but I'm not > > familiar enough with the ext4 code to diagnose any further. Please let > > me know if you need any additional information, or if you would like me > > to test anything. > >=20 >=20 > Can you show dmesg when regression happens? >=20 > Ye: It looks like this regression is caused by your commit. Would you like > to take a look on it? >=20 > Anyway, thanks for the bug report. I'm adding it to regzbot: >=20 > #regzbot ^introduced: eee00237fa5ec8 > #regzbot title: commit super block writes even in read-only filesystems >=20 Hi Thorsten, No reply so far from the culprit author (Ye Bin) nor from Ted. Can you help in this case? Thanks. --=20 An old man doll... just what I always wanted! - Clara --oHvmzLVb4TIpJ2OW Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQSSYQ6Cy7oyFNCHrUH2uYlJVVFOowUCZJTv7gAKCRD2uYlJVVFO o0k2AQCp/yGtFABFS0mWI8CAR7Iw6rXZ7YzDVYLumcrnHz7X/wD/bHBNW5DJFBe9 ThtrVO1RQ+VBOE2LY2hLK9CHgsXOWwI= =9Qko -----END PGP SIGNATURE----- --oHvmzLVb4TIpJ2OW--