On Wed, Mar 2, 2022 at 12:29 AM Muchun Song <songmuchun@xxxxxxxxxxxxx> wrote: > > The flush_cache_page() only remove a PAGE_SIZE sized range from the cache. > However, it does not cover the full pages in a THP except a head page. > Replace it with flush_cache_range() to fix this issue. This needs to clarify that this is just a documentation issue with the respect to properly documenting the expected usage of cache flushing before modifying the pmd. However, in practice this is not a problem due to the fact that DAX is not available on architectures with virtually indexed caches per: d92576f1167c dax: does not work correctly with virtual aliasing caches Otherwise, you can add: Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>