Re: [RFC 03/11] ext4: mballoc: Fix getting the right group desc in ext4_mb_prefetch_fini

Jan Kara
2023-03-09T11:42:29Z

On Fri 27-01-23 18:07:30, Ojaswin Mujoo wrote:
> group descriptor and group info are not of the same group in
> ext4_mb_prefetch_fini(). This problem was found during code
> review/walkthrough and seems like a bug, so fix it.
>
> Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
> Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>

Looks good to me. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

Honza

> ---
> fs/ext4/mballoc.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
> index 572e79a698d4..8b22cc07b054 100644
> --- a/fs/ext4/mballoc.c
> +++ b/fs/ext4/mballoc.c
> @@ -2569,14 +2569,14 @@ ext4_group_t ext4_mb_prefetch(struct super_block *sb, ext4_group_t group,
> void ext4_mb_prefetch_fini(struct super_block *sb, ext4_group_t group,
> unsigned int nr)
> {
> - while (nr-- > 0) {
> - struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group,
> - NULL);
> - struct ext4_group_info *grp = ext4_get_group_info(sb, group);
> + struct ext4_group_desc *gdp;
> + struct ext4_group_info *grp;
>
> + while (nr-- > 0) {
> if (!group)
> group = ext4_get_groups_count(sb);
> group--;
> + gdp = ext4_get_group_desc(sb, group, NULL);
> grp = ext4_get_group_info(sb, group);
>
> if (EXT4_MB_GRP_NEED_INIT(grp) &&
> --
> 2.31.1
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR