Re: [PATCH v2 4/5] guest_memfd: add support for userfaultfd minor mode

David Hildenbrand (Red Hat)
2025-11-26T10:25:32Z

On 11/25/25 19:38, Mike Rapoport wrote:
> From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
>
> userfaultfd notifications about minor page faults used for live migration
> and snapshotting of VMs with memory backed by shared hugetlbfs or tmpfs
> mappings as described in detail in commit 7677f7fd8be7 ("userfaultfd: add
> minor fault registration mode").
>
> To use the same mechanism for VMs that use guest_memfd to map their memory,
> guest_memfd should support userfaultfd minor mode.
>
> Extend ->fault() method of guest_memfd with ability to notify core page
> fault handler that a page fault requires handle_userfault(VM_UFFD_MINOR) to
> complete and add implementation of ->get_shared_folio() to guest_memfd
> vm_ops.
>
> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
> ---

No exports and still looks clean to me, nice. :)

--
Cheers

David