Pull more MM updates from Andrew Morton:
- "powerpc/pseries/cmm: two smaller fixes" (David Hildenbrand)
fixes a couple of minor things in ppc land
- "Improve folio split related functions" (Zi Yan)
some cleanups and minorish fixes in the folio splitting code
* tag 'mm-stable-2025-12-11-11-39' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/damon/tests/core-kunit: avoid damos_test_commit stack warning
mm: vmscan: correct nr_requested tracing in scan_folios
MAINTAINERS: add idr core-api doc file to XARRAY
mm/hugetlb: fix incorrect error return from hugetlb_reserve_pages()
mm: fix CONFIG_STACK_GROWSUP typo in mm.h
mm/huge_memory: fix folio split stats counting
mm/huge_memory: make min_order_for_split() always return an order
mm/huge_memory: replace can_split_folio() with direct refcount calculation
mm/huge_memory: change folio_split_supported() to folio_check_splittable()
mm/sparse: fix sparse_vmemmap_init_nid_early definition without CONFIG_SPARSEMEM
powerpc/pseries/cmm: adjust BALLOON_MIGRATE when migrating pages
powerpc/pseries/cmm: call balloon_devinfo_init() also without CONFIG_BALLOON_COMPACTION