Re: [PATCH v1 1/5] f2fs: Zero f2fs_folio_state on allocation

[Barry Song]

On Tue, Jan 6, 2026 at 12:12 AM Nanzhe Zhao <nzzhao@xxxxxxx> wrote:
>
> f2fs_folio_state is attached to folio->private and is expected to start
> with read_pages_pending == 0.  However, the structure was allocated from
> ffs_entry_slab without being fully initialized, which can leave
> read_pages_pending with stale values.
>
> Allocate the object with __GFP_ZERO so all fields are reliably zeroed at
> creation time.
>
> Signed-off-by: Nanzhe Zhao <nzzhao@xxxxxxx>


We already have GFP_F2FS_ZERO, but it includes GFP_IO. Should we
introduce another variant, such as GFP_F2FS_NOIO_ZERO (or similar)?
Overall, LGTM.

Reviewed-by: Barry Song <baohua@xxxxxxxxxx>

> ---
>  fs/f2fs/data.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 471e52c6c1e0..ab091b294fa7 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -2389,7 +2389,7 @@ static struct f2fs_folio_state *ffs_find_or_alloc(struct folio *folio)
>         if (ffs)
>                 return ffs;
>
> -       ffs = f2fs_kmem_cache_alloc(ffs_entry_slab, GFP_NOIO, true, NULL);
> +       ffs = f2fs_kmem_cache_alloc(ffs_entry_slab, GFP_NOIO | __GFP_ZERO, true, NULL);
>
>         spin_lock_init(&ffs->state_lock);
>         folio_attach_private(folio, ffs);
> --
> 2.34.1

Thanks
Barry