On Fri, Nov 04, 2022 at 04:35:53PM +0800, Baokun Li wrote:
> 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 during an on-line resize")
> Signed-off-by: Baokun Li <libaokun1@xxxxxxxxxx>
Yep, that looks correct. Sort of a pity that the checksum computation
isn't quite as automatic as it is in other filesystems, but that's my
fault... :/
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
--D
> ---
> 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 6dfe9ccae0c5..32fbfc173571 100644
> --- a/fs/ext4/resize.c
> +++ b/fs/ext4/resize.c
> @@ -1471,8 +1471,6 @@ 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);
>
> /* Update the free space counts */
> percpu_counter_add(&sbi->s_freeclusters_counter,
> @@ -1508,6 +1506,8 @@ static void ext4_update_super(struct super_block *sb,
> ext4_calculate_overhead(sb);
> es->s_overhead_clusters = cpu_to_le32(sbi->s_overhead);
>
> + 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,
> --
> 2.31.1
>
