Re: [PATCH v1 0/4] mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c

Mike Rapoport
2026-03-06T15:31:01Z

On Fri, Mar 06, 2026 at 11:15:56AM +0100, David Hildenbrand (Arm) wrote:
> Looking into vma_(kernel|mmu)_pagesize(), I realized that there is one
> scenario where DAX would not do the right thing when the kernel is
> not compiled with hugetlb support.
>
> Without hugetlb support, vma_(kernel|mmu)_pagesize() will always return
> PAGE_SIZE instead of using the ->pagesize() result provided by dax-device
> code.
>
> Fix that by moving vma_kernel_pagesize() to core MM code, where it belongs.
> I don't think this is stable material, but am not 100% sure.
>
> Also, move vma_mmu_pagesize() while at it. Remove the unnecessary hugetlb.h
> inclusion from KVM code.
>
> Cross-compiled heavily.
>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
> Cc: Nicholas Piggin <npiggin@gmail.com>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: "Christophe Leroy (CS GROUP)" <chleroy@kernel.org>
> Cc: Muchun Song <muchun.song@linux.dev>
> Cc: Oscar Salvador <osalvador@suse.de>
> Cc: Lorenzo Stoakes <ljs@kernel.org>
> Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
> Cc: Vlastimil Babka <vbabka@kernel.org>
> Cc: Mike Rapoport <rppt@kernel.org>
> Cc: Suren Baghdasaryan <surenb@google.com>
> Cc: Michal Hocko <mhocko@suse.com>
> Cc: Jann Horn <jannh@google.com>
> Cc: Pedro Falcato <pfalcato@suse.de>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Dan Williams <dan.j.williams@intel.com>
>
> David Hildenbrand (Arm) (4):
> mm: move vma_kernel_pagesize() from hugetlb to mm.h
> mm: move vma_mmu_pagesize() from hugetlb to vma.c
> KVM: remove hugetlb.h inclusion
> KVM: PPC: remove hugetlb.h inclusion
>
> arch/powerpc/kvm/book3s_hv.c | 1 -
> include/linux/hugetlb.h | 14 --------------
> include/linux/mm.h | 22 ++++++++++++++++++++++
> mm/hugetlb.c | 28 ----------------------------
> mm/vma.c | 21 +++++++++++++++++++++
> virt/kvm/kvm_main.c | 1 -
> 6 files changed, 43 insertions(+), 44 deletions(-)

For the series:

Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

> base-commit: f75825cdfc4c5477cffcfd2cafa4e5ce5aa67f13
> --
> 2.43.0
>

--
Sincerely yours,
Mike.