Alistair Popple wrote: > At present mlock skips ptes mapping ZONE_DEVICE pages. A future change > to remove pmd_devmap will allow pmd_trans_huge_lock() to return > ZONE_DEVICE folios so make sure we continue to skip those. > > Signed-off-by: Alistair Popple <apopple@xxxxxxxxxx> > Acked-by: David Hildenbrand <david@xxxxxxxxxx> This looks like a fix in that mlock_pte_range() *does* call mlock_folio() when pmd_trans_huge_lock() returns a non-NULL @ptl. So it is not in preparation for a future change it is making the pte and pmd cases behave the same to drop mlock requests. The code change looks good, but do add a Fixes tag and reword the changelog a bit before adding: Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>