Re: [PATCH] zonefs: do not use append if device does not support it

From: Christoph Hellwig
Date: Mon Jun 26 2023 - 23:46:57 EST


On Mon, Jun 26, 2023 at 06:47:52PM +0200, Andreas Hindborg wrote:
> From: "Andreas Hindborg (Samsung)" <nmi@xxxxxxxxxxxx>
>
> Zonefs will try to use `zonefs_file_dio_append()` for direct sync writes even if
> device `max_zone_append_sectors` is zero. This will cause the IO to fail as the
> io vector is truncated to zero. It also causes a call to
> `invalidate_inode_pages2_range()` with end set to UINT_MAX, which is probably
> not intentional. Thus, do not use append when device does not support it.

How do you even manage to hit this code? Zone Append is a mandatory
feature and driver need to check it is available.