Re: [PATCH 3/4] md/md-llbitmap: unmap sb page before freeing it

[yu kuai]

在 2026/7/19 22:44, Mykola Marzhan 写道:
> Every path in llbitmap_read_sb() that maps the superblock page ends
> at the out_put_page label, which frees the page and only then unmaps
> it:
>
> 	__free_page(sb_page);
> 	kunmap_local(sb);
>
> The page comes from alloc_page(GFP_KERNEL), so kunmap_local() is
> currently a no-op everywhere except CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
> builds -- where the page really is freed while a live mapping still
> points at it.  Unmap before freeing.
>
> Fixes: 5ab829f1971d ("md/md-llbitmap: introduce new lockless bitmap")
> Assisted-by: Claude-Code:claude-opus-4-8
> Signed-off-by: Mykola Marzhan<mykola@xxxxxxxxxxx>
> ---
>   drivers/md/md-llbitmap.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
Reviewed-by: Yu Kuai <yukuai@xxxxxxx>

-- 
Thanks,
Kuai