The patch titled Subject: mm/pagemap: recognize uffd-wp bit for shmem/hugetlbfs has been added to the -mm tree. Its filename is mm-pagemap-recognize-uffd-wp-bit-for-shmem-hugetlbfs.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/mm-pagemap-recognize-uffd-wp-bit-for-shmem-hugetlbfs.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/mm-pagemap-recognize-uffd-wp-bit-for-shmem-hugetlbfs.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Peter Xu <peterx@xxxxxxxxxx> Subject: mm/pagemap: recognize uffd-wp bit for shmem/hugetlbfs This requires the pagemap code to be able to recognize the newly introduced swap special pte for uffd-wp, meanwhile the general case for hugetlb that we recently start to support. It should make pagemap uffd-wp support complete. Link: https://lkml.kernel.org/r/20220405014923.15047-1-peterx@xxxxxxxxxx Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> Cc: Alistair Popple <apopple@xxxxxxxxxx> Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx> Cc: Axel Rasmussen <axelrasmussen@xxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Jerome Glisse <jglisse@xxxxxxxxxx> Cc: "Kirill A . Shutemov" <kirill@xxxxxxxxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Cc: Nadav Amit <nadav.amit@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/proc/task_mmu.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/fs/proc/task_mmu.c~mm-pagemap-recognize-uffd-wp-bit-for-shmem-hugetlbfs +++ a/fs/proc/task_mmu.c @@ -1421,6 +1421,8 @@ static pagemap_entry_t pte_to_pagemap_en migration = is_migration_entry(entry); if (is_pfn_swap_entry(entry)) page = pfn_swap_entry_to_page(entry); + if (pte_marker_entry_uffd_wp(entry)) + flags |= PM_UFFD_WP; } if (page && !PageAnon(page)) @@ -1556,10 +1558,15 @@ static int pagemap_hugetlb_range(pte_t * if (page_mapcount(page) == 1) flags |= PM_MMAP_EXCLUSIVE; + if (huge_pte_uffd_wp(pte)) + flags |= PM_UFFD_WP; + flags |= PM_PRESENT; if (pm->show_pfn) frame = pte_pfn(pte) + ((addr & ~hmask) >> PAGE_SHIFT); + } else if (pte_swp_uffd_wp_any(pte)) { + flags |= PM_UFFD_WP; } for (; addr != end; addr += PAGE_SIZE) { _ Patches currently in -mm which might be from peterx@xxxxxxxxxx are mm-introduce-pte_marker-swap-entry.patch mm-teach-core-mm-about-pte-markers.patch mm-check-against-orig_pte-for-finish_fault.patch mm-uffd-pte_marker_uffd_wp.patch mm-shmem-take-care-of-uffdio_copy_mode_wp.patch mm-shmem-handle-uffd-wp-special-pte-in-page-fault-handler.patch mm-shmem-persist-uffd-wp-bit-across-zapping-for-file-backed.patch mm-shmem-allow-uffd-wr-protect-none-pte-for-file-backed-mem.patch mm-shmem-allows-file-back-mem-to-be-uffd-wr-protected-on-thps.patch mm-shmem-handle-uffd-wp-during-fork.patch mm-hugetlb-introduce-huge-pte-version-of-uffd-wp-helpers.patch mm-hugetlb-hook-page-faults-for-uffd-write-protection.patch mm-hugetlb-take-care-of-uffdio_copy_mode_wp.patch mm-hugetlb-handle-uffdio_writeprotect.patch mm-hugetlb-handle-pte-markers-in-page-faults.patch mm-hugetlb-allow-uffd-wr-protect-none-ptes.patch mm-hugetlb-only-drop-uffd-wp-special-pte-if-required.patch mm-hugetlb-handle-uffd-wp-during-fork.patch mm-khugepaged-dont-recycle-vma-pgtable-if-uffd-wp-registered.patch mm-pagemap-recognize-uffd-wp-bit-for-shmem-hugetlbfs.patch mm-uffd-enable-write-protection-for-shmem-hugetlbfs.patch mm-enable-pte-markers-by-default.patch selftests-uffd-enable-uffd-wp-for-shmem-hugetlbfs.patch