On 12.08.25 04:40, Balbir Singh wrote:
Support splitting pages during THP zone device migration as needed.
The common case that arises is that after setup, during migrate
the destination might not be able to allocate MIGRATE_PFN_COMPOUND
pages.
Add a new routine migrate_vma_split_pages() to support the splitting
of already isolated pages. The pages being migrated are already unmapped
and marked for migration during setup (via unmap). folio_split() and
__split_unmapped_folio() take additional isolated arguments, to avoid
unmapping and remaping these pages and unlocking/putting the folio.
No detailed review, just a high-level comment: please take better care
of crafting your patch subjects.
This should probably be
mm/migrate_device: support splitting device folios during migration
--
Cheers
David / dhildenb
