Wrong check of gdb backup in meta bg as following: first_group is the first group of meta_bg which contains target group, so target group is always >= first_group. We check if target group has gdb backup by comparing first_group with [group + 1] and [group + EXT4_DESC_PER_BLOCK(sb) - 1]. As group >= first_group, then [group + N] is > first_group. So no copy of gdb backup in meta bg is done in setup_new_flex_group_blocks. No need to do gdb backup copy in meta bg from setup_new_flex_group_blocks as we always copy updated gdb block to backups at end of ext4_flex_group_add as following: ext4_flex_group_add /* no gdb backup copy for meta bg any more */ setup_new_flex_group_blocks /* update current group number */ ext4_update_super sbi->s_groups_count += flex_gd->count; /* * if group in meta bg contains backup is added, the primary gdb block * of the meta bg will be copy to backup in new added group here. */ for (; gdb_num <= gdb_num_end; gdb_num++) update_backups(...) In summary, we can remove wrong gdb backup copy code in setup_new_flex_group_blocks. Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> Reviewed-by: Theodore Ts'o <tytso@xxxxxxx> --- fs/ext4/resize.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 9cb9ed968599..667381180b26 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -560,13 +560,8 @@ static int setup_new_flex_group_blocks(struct super_block *sb, if (meta_bg == 0 && !ext4_bg_has_super(sb, group)) goto handle_itb; - if (meta_bg == 1) { - ext4_group_t first_group; - first_group = ext4_meta_bg_first_group(sb, group); - if (first_group != group + 1 && - first_group != group + EXT4_DESC_PER_BLOCK(sb) - 1) - goto handle_itb; - } + if (meta_bg == 1) + goto handle_itb; block = start + ext4_bg_has_super(sb, group); /* Copy all of the GDT blocks into the backup in this group */ -- 2.30.0