Re: [PATCH v2 0/7] exfat: fix valid_size update races

[Namjae Jeon]

On Tue, Oct 13, 2026 at 12:39 PM Chi Zhiling <chizhiling@xxxxxxx> wrote:
>
> From: Chi Zhiling <chizhiling@xxxxxxxxxx>
Hi Chi,
>
> exFAT uses valid_size (ValidDataLength) as the on-disk boundary of
> initialised data, but the current code advances it too late or without
> proper serialisation.  As a result, buffered writes can silently lose
> data reclaimed before valid_size covers it, page faults and direct I/O
> can race with writes, and a failed direct write still grows the file
> on disk.
>
> This series advances valid_size under the folio lock for buffered
> writes, revalidates cached iomaps, drops i_rwsem from
> exfat_page_mkwrite(), and publishes i_size/valid_size only on
> successful direct I/O completion.
>
> V1: https://lore.kernel.org/exfat/59056131-e3bd-4003-8c30-0a356cf0bd82@xxxxxxx/
> Link: https://lore.kernel.org/exfat/10029d6f-13cc-4d17-a2f9-b093a8339dde/T/#t
>
> Chi Zhiling (7):
>   exfat: advance valid_size under the folio lock for buffered writes
>   exfat: advance valid_size while zeroing new ranges
>   exfat: validate cached iomaps during buffered writes
>   exfat: drop i_rwsem from exfat_page_mkwrite
>   exfat: do not re-zero the valid range in exfat_page_mkwrite
>   exfat: complete direct writes synchronously when they update metadata
>   exfat: publish i_size and valid_size on direct I/O completion
Can you add fixes tags to the patches ?
Thanks.