On Wed, May 13, 2026 at 06:31:27PM -0700, SeongJae Park wrote:
> On Fri, 8 May 2026 16:55:15 +0100 "Kiryl Shutsemau (Meta)" <[email protected]>
> wrote:
>
> > Userfaultfd RWP will reuse the uffd-wp PTE bit to mark access-tracking
> > PTEs, alongside the write-protected ones it already marks. The bit's
> > meaning now depends on the VMA flag (WP or RWP), not on its name.
> >
> > Rename the kernel-internal names that describe the bit:
> >
> > - pte/pmd/huge_pte accessors (and swap variants)
> > - pgtable_supports_uffd() capability query
> > - SCAN_PTE_UFFD khugepaged enum
> >
> > The ftrace string emitted by mm_khugepaged_scan_pmd for this enum is
> > kept as "pte_uffd_wp" so existing trace-based tooling keeps matching.
> >
> > Pure mechanical rename -- no behavior change.
> >
> > Signed-off-by: Kiryl Shutsemau <[email protected]>
> > Assisted-by: Claude:claude-opus-4-6
> > Reviewed-by: Mike Rapoport (Microsoft) <[email protected]>
>
> Reviewed-by: SeongJae Park <[email protected]>
Thanks!
> [...]
> > @@ -4934,10 +4934,10 @@ int copy_hugetlb_page_range(struct mm_struct *dst,
> > struct mm_struct *src,
> > softleaf = softleaf_from_pte(entry);
> > if (unlikely(softleaf_is_hwpoison(softleaf))) {
> > if (!userfaultfd_wp(dst_vma))
> > - entry = huge_pte_clear_uffd_wp(entry);
> > + entry = huge_pte_clear_uffd(entry);
> > set_huge_pte_at(dst, addr, dst_pte, entry, sz);
> > } else if (unlikely(softleaf_is_migration(softleaf))) {
> > - bool uffd_wp = pte_swp_uffd_wp(entry);
> > + bool uffd_wp = pte_swp_uffd(entry);
>
> Just curious. Is the variable name intentionally kept to avoid unnecessary
> change?
No, I've missed this. Will fix.
--
Kiryl Shutsemau / Kirill A. Shutemov
