On 11/15/25 11:51, Andrew Morton wrote: > On Sat, 15 Nov 2025 11:28:35 +1100 Balbir Singh <[email protected]> wrote: > >> Follow the pattern used in remove_migration_pte() in >> remove_migration_pmd(). Process the migration entries and if the entry >> type is device private, override the pmde with a device private entry >> and set the soft dirty and uffd_wp bits with the pmd_swp_mksoft_dirty >> and pmd_swp_mkuffd_wp >> >> ... >> >> This fixup should be squashed into the patch "mm/rmap: extend rmap and >> migration support" of mm/mm-unstable >> > > OK. After fixing up > mm-replace-pmd_to_swp_entry-with-softleaf_from_pmd.patch, mm.git's > mm/huge_memory.c has the below. Please double-check. > > > void remove_migration_pmd(struct page_vma_mapped_walk *pvmw, struct page *new) > { > struct folio *folio = page_folio(new); > struct vm_area_struct *vma = pvmw->vma; > struct mm_struct *mm = vma->vm_mm; > unsigned long address = pvmw->address; > unsigned long haddr = address & HPAGE_PMD_MASK; > pmd_t pmde; > softleaf_t entry; > > if (!(pvmw->pmd && !pvmw->pte)) > return; > > entry = softleaf_from_pmd(*pvmw->pmd); > folio_get(folio); > pmde = folio_mk_pmd(folio, READ_ONCE(vma->vm_page_prot)); > > if (pmd_swp_soft_dirty(*pvmw->pmd)) > pmde = pmd_mksoft_dirty(pmde); > if (softleaf_is_migration_write(entry)) > pmde = pmd_mkwrite(pmde, vma); > if (pmd_swp_uffd_wp(*pvmw->pmd)) > pmde = pmd_mkuffd_wp(pmde); > if (!softleaf_is_migration_young(entry)) > pmde = pmd_mkold(pmde); > /* NOTE: this may contain setting soft-dirty on some archs */ > if (folio_test_dirty(folio) && softleaf_is_migration_dirty(entry)) > pmde = pmd_mkdirty(pmde); > > if (folio_is_device_private(folio)) { > swp_entry_t entry; > > if (pmd_write(pmde)) > entry = make_writable_device_private_entry( > page_to_pfn(new)); > else > entry = make_readable_device_private_entry( > page_to_pfn(new)); > pmde = swp_entry_to_pmd(entry); > > if (pmd_swp_soft_dirty(*pvmw->pmd)) > pmde = pmd_swp_mksoft_dirty(pmde); > if (pmd_swp_uffd_wp(*pvmw->pmd)) > pmde = pmd_swp_mkuffd_wp(pmde); > } > > if (folio_test_anon(folio)) { > rmap_t rmap_flags = RMAP_NONE; > > if (!softleaf_is_migration_read(entry)) > rmap_flags |= RMAP_EXCLUSIVE; > > folio_add_anon_rmap_pmd(folio, new, vma, haddr, rmap_flags); > } else { > folio_add_file_rmap_pmd(folio, new, vma); > } > VM_BUG_ON(pmd_write(pmde) && folio_test_anon(folio) && > !PageAnonExclusive(new)); > set_pmd_at(mm, haddr, pvmw->pmd, pmde); > > /* No need to invalidate - it was non-present before */ > update_mmu_cache_pmd(vma, address, pvmw->pmd); > trace_remove_migration_pmd(address, pmd_val(pmde)); > }
Thanks, Andrew! Looks good! Balbir
