From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail02.ukr.de (mail02.ukr.de [193.175.194.182]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 699071A28C for ; Tue, 19 Nov 2024 08:21:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.175.194.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732004469; cv=none; b=a6nGdw4Hxqc92kCekJf217Kq5BR3WDSAtTKA49Z8GSjm6fRtr6dnbVF4Z3D5ao2m/1SF739yX7c5M+0x4LZu9CfsiWSmrNm0pbUPOCzPbSMZ9iqbyorFsfQ97mFSvriui6IZFYN2tHX7I+6BPlTa2qBcx3QWYIepMEURlyoLSo0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732004469; c=relaxed/simple; bh=Rjh+5AkQKR+Lynfk2rH5q4K8PsJOupeqRWpRMx4j2Tc=; h=From:To:CC:Subject:Date:Message-ID:References:In-Reply-To: Content-Type:MIME-Version; b=XvKvrFtql3h7d693Oa1SiVdzzTqXsQtICGQrXdgFtfvmTjfXPN7fySFiB1AFMpSLt08tGvqfE0oOsTmUCb4vRE+mp3Ry5DM9j8ggCPaSjGytrOpIx6ebPTGeOYgWxYFJrnmEH9/xG+kUplxJNwa2XiclvqerWJmhfNZkL1jxHaA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ukr.de; spf=pass smtp.mailfrom=ukr.de; arc=none smtp.client-ip=193.175.194.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ukr.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ukr.de X-CSE-ConnectionGUID: bcYlmuh8RHCzO9+zBny7yQ== X-CSE-MsgGUID: Dye5k3AfTp2Mx+2D8/ogYQ== X-ThreatScanner-Verdict: Negative X-IronPort-AV: E=McAfee;i="6700,10204,11260"; a="1182718" X-IronPort-AV: E=Sophos;i="6.12,165,1728943200"; d="scan'208";a="1182718" Received: from unknown (HELO ukr-excmb04.ukr.local) ([172.24.6.64]) by dmz-infcsg02.ukr.dmz with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Nov 2024 09:19:54 +0100 Received: from ukr-excmb03.ukr.local (172.24.6.63) by ukr-excmb04.ukr.local (172.24.6.64) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Tue, 19 Nov 2024 09:19:54 +0100 Received: from ukr-excmb03.ukr.local ([fe80::1cb4:6e0c:6da4:a8a0]) by ukr-excmb03.ukr.local ([fe80::1cb4:6e0c:6da4:a8a0%4]) with mapi id 15.01.2507.039; Tue, 19 Nov 2024 09:19:54 +0100 From: "Windl, Ulrich" To: Krister Johansen , Lennart Poettering CC: "util-linux@vger.kernel.org" , Karel Zak , "systemd-devel@lists.freedesktop.org" , David Reaver , Theodore Ts'o Subject: RE: [EXT] Re: [systemd-devel] [PATCH] libblkid: fix spurious ext superblock checksum mismatches Thread-Topic: [EXT] Re: [systemd-devel] [PATCH] libblkid: fix spurious ext superblock checksum mismatches Thread-Index: AQHbOgprtyS8p8SbNkmh7F6ouMqr3bK9mjcAgACo6DA= Date: Tue, 19 Nov 2024 08:19:54 +0000 Message-ID: <246892aea2ef4119bb2b0b248c720737@ukr.de> References: <6d16e6d83ab48d2ea4402db17c9c0ed5514933a7.1731961869.git.kjlx@templeofstupid.com> <20241118231352.GC1885@templeofstupid.com> In-Reply-To: <20241118231352.GC1885@templeofstupid.com> Accept-Language: de-DE, en-US Content-Language: de-DE X-MS-Has-Attach: X-MS-TNEF-Correlator: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: util-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 > -----Original Message----- > From: systemd-devel On > Behalf Of Krister Johansen > Sent: Tuesday, November 19, 2024 12:14 AM > To: Lennart Poettering > Cc: util-linux@vger.kernel.org; Karel Zak ; systemd- > devel@lists.freedesktop.org; David Reaver ; > Theodore Ts'o > Subject: [EXT] Re: [systemd-devel] [PATCH] libblkid: fix spurious ext > superblock checksum mismatches >=20 ...=20 > I may have done a poor job of explaining this. This is ext writing its > own superblock from the kernel, but reads seeing an potentially > inconsistent view of that write. O_DIRECT causes us to seralize with > the locks ext4 holds when it writes the superblock, which prevents the > read from observing a partial update. >=20 > It's not necessarily the partitioning tools causing this, but any > filesystem level udpdate that modifies the contents of the superblock. As I wrote before: I don't think the needless O_DIRECT fixes things some ot= her code broke.