From nobody Mon Apr 13 18:45:45 2026 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 5F025C4332F for ; Thu, 17 Nov 2022 03:42:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238401AbiKQDm1 (ORCPT ); Wed, 16 Nov 2022 22:42:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55484 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232905AbiKQDmW (ORCPT ); Wed, 16 Nov 2022 22:42:22 -0500 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EDF5B5E9DD; Wed, 16 Nov 2022 19:42:21 -0800 (PST) Received: from dggpeml500021.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4NCQhF0bQGzHvxq; Thu, 17 Nov 2022 11:41:49 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpeml500021.china.huawei.com (7.185.36.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 17 Nov 2022 11:42:19 +0800 From: Baokun Li To: CC: , , , , , , , , "Darrick J . Wong" Subject: [PATCH v3 1/3] ext4: fix bad checksum after online resize Date: Thu, 17 Nov 2022 12:03:39 +0800 Message-ID: <20221117040341.1380702-2-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20221117040341.1380702-1-libaokun1@huawei.com> References: <20221117040341.1380702-1-libaokun1@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpeml500021.china.huawei.com (7.185.36.21) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" When online resizing is performed twice consecutively, the error message "Superblock checksum does not match superblock" is displayed for the second time. Here's the reproducer: mkfs.ext4 -F /dev/sdb 100M mount /dev/sdb /tmp/test resize2fs /dev/sdb 5G resize2fs /dev/sdb 6G To solve this issue, we moved the update of the checksum after the es->s_overhead_clusters is updated. Fixes: 026d0d27c488 ("ext4: reduce computation of overhead during resize") Fixes: de394a86658f ("ext4: update s_overhead_clusters in the superblock du= ring an on-line resize") Signed-off-by: Baokun Li Reviewed-by: Darrick J. Wong Reviewed-by: Jan Kara --- fs/ext4/resize.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 46b87ffeb304..cb99b410c9fa 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1476,8 +1476,6 @@ static void ext4_update_super(struct super_block *sb, * active. */ ext4_r_blocks_count_set(es, ext4_r_blocks_count(es) + reserved_blocks); - ext4_superblock_csum_set(sb); - unlock_buffer(sbi->s_sbh); =20 /* Update the free space counts */ percpu_counter_add(&sbi->s_freeclusters_counter, @@ -1513,6 +1511,8 @@ static void ext4_update_super(struct super_block *sb, ext4_calculate_overhead(sb); es->s_overhead_clusters =3D cpu_to_le32(sbi->s_overhead); =20 + ext4_superblock_csum_set(sb); + unlock_buffer(sbi->s_sbh); if (test_opt(sb, DEBUG)) printk(KERN_DEBUG "EXT4-fs: added group %u:" "%llu blocks(%llu free %llu reserved)\n", flex_gd->count, --=20 2.31.1 From nobody Mon Apr 13 18:45:45 2026 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 610ECC4332F for ; Thu, 17 Nov 2022 03:42:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238928AbiKQDma (ORCPT ); Wed, 16 Nov 2022 22:42:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234067AbiKQDmX (ORCPT ); Wed, 16 Nov 2022 22:42:23 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B3A4275E2; Wed, 16 Nov 2022 19:42:22 -0800 (PST) Received: from dggpeml500021.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4NCQcS1bgYzqSWR; Thu, 17 Nov 2022 11:38:32 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpeml500021.china.huawei.com (7.185.36.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 17 Nov 2022 11:42:20 +0800 From: Baokun Li To: CC: , , , , , , , Subject: [PATCH v3 2/3] ext4: fix corrupt backup group descriptors after online resize Date: Thu, 17 Nov 2022 12:03:40 +0800 Message-ID: <20221117040341.1380702-3-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20221117040341.1380702-1-libaokun1@huawei.com> References: <20221117040341.1380702-1-libaokun1@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpeml500021.china.huawei.com (7.185.36.21) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" In commit 9a8c5b0d0615 ("ext4: update the backup superblock's at the end of the online resize"), it is assumed that update_backups() only updates backup superblocks, so each b_data is treated as a backupsuper block to update its s_block_group_nr and s_checksum. However, update_backups() also updates the backup group descriptors, which causes the backup group descriptors to be corrupted. The above commit fixes the problem of invalid checksum of the backup superblock. The root cause of this problem is that the checksum of ext4_update_super() is not set correctly. This problem has been fixed in the previous patch ("ext4: fix bad checksum after online resize"). However, we do need to set block_group_nr for the backup superblock in update_backups(). When a block is in a group that contains a backup superblock, and the block is the first block in the group, the block is definitely a superblock. We add a helper function that includes setting s_block_group_nr and updating checksum, and then call it only when the above conditions are met to prevent the backup group descriptors from being incorrectly modified. Fixes: 9a8c5b0d0615 ("ext4: update the backup superblock's at the end of th= e online resize") Signed-off-by: Baokun Li Reviewed-by: Jan Kara --- V2->V3: Modify the scheme and retain s_block_group_nr. fs/ext4/resize.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index cb99b410c9fa..66ceabbd83ad 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1110,6 +1110,16 @@ static int reserve_backup_gdb(handle_t *handle, stru= ct inode *inode, return err; } =20 +static inline void ext4_set_block_group_nr(struct super_block *sb, char *d= ata, + ext4_group_t group) +{ + struct ext4_super_block *es =3D (struct ext4_super_block *) data; + + es->s_block_group_nr =3D cpu_to_le16(group); + if (ext4_has_metadata_csum(sb)) + es->s_checksum =3D ext4_superblock_csum(sb, es); +} + /* * Update the backup copies of the ext4 metadata. These don't need to be = part * of the main resize transaction, because e2fsck will re-write them if th= ere @@ -1158,7 +1168,8 @@ static void update_backups(struct super_block *sb, se= ctor_t blk_off, char *data, while (group < sbi->s_groups_count) { struct buffer_head *bh; ext4_fsblk_t backup_block; - struct ext4_super_block *es; + int has_super =3D ext4_bg_has_super(sb, group); + ext4_fsblk_t first_block =3D ext4_group_first_block_no(sb, group); =20 /* Out of journal space, and can't get more - abort - so sad */ err =3D ext4_resize_ensure_credits_batch(handle, 1); @@ -1168,8 +1179,7 @@ static void update_backups(struct super_block *sb, se= ctor_t blk_off, char *data, if (meta_bg =3D=3D 0) backup_block =3D ((ext4_fsblk_t)group) * bpg + blk_off; else - backup_block =3D (ext4_group_first_block_no(sb, group) + - ext4_bg_has_super(sb, group)); + backup_block =3D first_block + has_super; =20 bh =3D sb_getblk(sb, backup_block); if (unlikely(!bh)) { @@ -1187,10 +1197,8 @@ static void update_backups(struct super_block *sb, s= ector_t blk_off, char *data, memcpy(bh->b_data, data, size); if (rest) memset(bh->b_data + size, 0, rest); - es =3D (struct ext4_super_block *) bh->b_data; - es->s_block_group_nr =3D cpu_to_le16(group); - if (ext4_has_metadata_csum(sb)) - es->s_checksum =3D ext4_superblock_csum(sb, es); + if (has_super && (backup_block =3D=3D first_block)) + ext4_set_block_group_nr(sb, bh->b_data, group); set_buffer_uptodate(bh); unlock_buffer(bh); err =3D ext4_handle_dirty_metadata(handle, NULL, bh); --=20 2.31.1 From nobody Mon Apr 13 18:45:45 2026 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 7332FC433FE for ; Thu, 17 Nov 2022 03:42:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234157AbiKQDmd (ORCPT ); Wed, 16 Nov 2022 22:42:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55496 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234640AbiKQDmX (ORCPT ); Wed, 16 Nov 2022 22:42:23 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F2CF54B0A; Wed, 16 Nov 2022 19:42:23 -0800 (PST) Received: from dggpeml500021.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4NCQhQ6GgLz15MZk; Thu, 17 Nov 2022 11:41:58 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpeml500021.china.huawei.com (7.185.36.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 17 Nov 2022 11:42:20 +0800 From: Baokun Li To: CC: , , , , , , , Subject: [PATCH v3 3/3] ext4: fix corruption when online resizing a 1K bigalloc fs Date: Thu, 17 Nov 2022 12:03:41 +0800 Message-ID: <20221117040341.1380702-4-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20221117040341.1380702-1-libaokun1@huawei.com> References: <20221117040341.1380702-1-libaokun1@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpeml500021.china.huawei.com (7.185.36.21) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" When a backup superblock is updated in update_backups(), the primary superblock's offset in the group (that is, sbi->s_sbh->b_blocknr) is used as the backup superblock's offset in its group. However, when the block size is 1K and bigalloc is enabled, the two offsets are not equal. This causes the backup group descriptors to be overwritten by the superblock in update_backups(). Moreover, if meta_bg is enabled, the file system will be corrupted because this feature uses backup group descriptors. To solve this issue, we use a more accurate ext4_group_first_block_no() as the offset of the backup superblock in its group. Fixes: d77147ff443b ("ext4: add support for online resizing with bigalloc") Signed-off-by: Baokun Li Reviewed-by: Jan Kara --- V1->V2: Replace s_first_data_block with ext4_group_first_block_no() to avoid type warning.(Reported-by: kernel test robot ) fs/ext4/resize.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 66ceabbd83ad..b493233750ab 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1604,8 +1604,8 @@ static int ext4_flex_group_add(struct super_block *sb, int meta_bg =3D ext4_has_feature_meta_bg(sb); sector_t old_gdb =3D 0; =20 - update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es, - sizeof(struct ext4_super_block), 0); + update_backups(sb, ext4_group_first_block_no(sb, 0), + (char *)es, sizeof(struct ext4_super_block), 0); for (; gdb_num <=3D gdb_num_end; gdb_num++) { struct buffer_head *gdb_bh; =20 @@ -1816,7 +1816,7 @@ static int ext4_group_extend_no_check(struct super_bl= ock *sb, if (test_opt(sb, DEBUG)) printk(KERN_DEBUG "EXT4-fs: extended group to %llu " "blocks\n", ext4_blocks_count(es)); - update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr, + update_backups(sb, ext4_group_first_block_no(sb, 0), (char *)es, sizeof(struct ext4_super_block), 0); } return err; --=20 2.31.1