From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794657834; b=Fo54wxVTmzdjs7i8A0onolaaz3In6ZgwOoE+paC5u97DYfWhY/75gttGygKc1iQj+wSS P4OmtHn0TE4DYiC1yPEpjPaPSq/TFWGBJRt9NQFP3svK3Vcfl0uJUk8WArnzJhyYJseC/ OYJmmMhGLtbC0BzgQXIUZx78sO0tRNl662U+YOgVJSNM2w8iw01XZK+zAOiIq3Vs0VR0L PgT3PBVHBdq5Aiob2eyQHqYcl5v54Qy62YznoTHDJbhDzyNjEIswwSGmw7dV4d852Z8gG TvOjMtwktwpANAk/jQfvrkK044Souj1+R8468ldlANS+MJJs3ogghGWzdeXnun08o2w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794657834; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=xFINoKU1kPDIv3Vg1jdGriiWa60P1WBowOguZfSQ2N8=; b=HI/J47WzTvIo3mTs2yeZnXk0+JetlH61Yg+c5XoUTsBENXrU7x7w9MOf0i0EaMgsVDVz je2NiKXjmsoRSwX2F14sxxco4cUQXlWsHnbYlSwYYDsOUWF04oS7A6e/NfZJrw8IQRbwO UdV17vntwtp7O4H3jcmSiDyNnXIllA//laz3ZWhU9ThGGg1euOpi66pk5HOnKUYfT9bzY Et59RvywSd10UisyHuTcX2ug2y3qTrpjjAG1J0ID9WsmN6uA9eukzHM2POsHHQPs8axqI SSf5s2qAkR5VGhXC6MVnhbxOlELo0Op9QdfKL7ddcurG8KOzxicnsSjFCnsC1BVd5Kg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="LTlwSDK/"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8FC48606A338 for ; Sat, 14 Nov 2026 12:03:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=LTlwSDK/ Received: by smtp.kernel.org (Postfix) with ESMTPSA id EE5C21F000C8; Sat, 14 Nov 2026 12:03:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794657834; bh=xFINoKU1kPDIv3Vg1jdGriiWa60P1WBowOguZfSQ2N8=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=LTlwSDK/W/svMtn+8xV3c92f571oeCMeLDaeh9f6OweBO14mmP/7E1rUBi3+aRP8d 32f6mkX+SW5eVYcqWjmrT6M0W4EQoUoLy4q4BMiDUH74Qv6Dw5JW8gbhV7OzZ3+jfu KvBanhfiPyfNykQm00KtprQzMRp98XwsRkarvjb3z5YcB1AwX0f4mcXmnVQkqmQq4F dnYCvGGcCFwJzd42pMHcVMkrjkur+BLeZB5QmOTLUCR3lxwu+LqKI1zMBcoV9evwIB 3Jkumv+PXjvDZngP2RH+0fDSgwiVDrxwNCtQLnesrbnSEiUqw9Op/rH/OJEameJgiH efQerBuJaNVPA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v3 31/33] ext4: allow remounting read-only in the emergency state Reply-To: sashiko-reviews@lists.linux.dev To: "Christian Brauner" Cc: linux-ext4@vger.kernel.org, tytso@mit.edu, "Mark Fasheh" , "Joel Becker" , "Joseph Qi" In-Reply-To: <20261113-work-fs-sb_rdonly-v3-31-0be92bb73709@kernel.org> References: <20261113-work-fs-sb_rdonly-v3-0-0be92bb73709@kernel.org> <20261113-work-fs-sb_rdonly-v3-31-0be92bb73709@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Sat, 14 Nov 2026 12:03:53 +0000 X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > __ext4_remount() refuses any change of the read-only state with EROFS > while ext4_emergency_state() is set, i.e. after a shutdown or an error. > Neither sets SB_RDONLY anymore, so a remount to read-only fails and the > filesystem stays read-write. Emergency remount (sysrq u) asks with > SB_FORCE and reconfigure_super() WARNs, a panic with panic_on_warn: >=20 > forced remount of a ext4 fs returned -30 >=20 > Becoming read-only doesn't need to write anything. So allow it and skip > everything in that branch that would touch the disk: sync_filesystem(), > dquot_suspend(), the s_state update, ext4_mark_recovery_complete() and > the superblock commit without a journal. Going read-write is still > refused. >=20 > Note that ext4_emergency_state() only exists since v6.15. Older stable > trees need ext4_forced_shutdown() instead. >=20 > Fixes: 95257987a638 ("ext4: drop EXT4_MF_FS_ABORTED flag") > Fixes: d3476f3dad4a ("ext4: don't set SB_RDONLY after filesystem errors") > Cc: stable@vger.kernel.org > Reviewed-by: Jan Kara > Signed-off-by: Christian Brauner (Amutable) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261113-work-fs-sb= _rdonly-v3-0-0be92bb73709@kernel.org?part=3D31