Re: [PATCH RFC v3 for-6.8/block 02/17] xen/blkback: use bdev api in xen_update_blkif_status()

[Christoph Hellwig]

On Thu, Jan 04, 2024 at 12:06:31PM +0100, Jan Kara wrote:
> This function uses invalidate_inode_pages2() while invalidate_bdev() ends
> up using mapping_try_invalidate() and there are subtle behavioral
> differences between these two (for example invalidate_inode_pages2() tries
> to clean dirty pages using the ->launder_folio method). So I think you'll
> need helper like invalidate_bdev2() for this.

That assues that the existing code actually does this intentionally,
which seems doubtful.  But the change in behavior does not to be
documented and explained.