The patch titled Subject: Fixup: mm: convert ksm_might_need_to_copy() to work on folios has been added to the -mm mm-unstable branch. Its filename is mm-convert-ksm_might_need_to_copy-to-work-on-folios-fix-fix.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-convert-ksm_might_need_to_copy-to-work-on-folios-fix-fix.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 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 via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: David Hildenbrand <david@xxxxxxxxxx> Subject: Fixup: mm: convert ksm_might_need_to_copy() to work on folios Date: Thu, 21 Dec 2023 23:04:30 +0100 We must only adjust the page if the folio changed. Otherwise, if we had a large folio in the swapcache and the folio didn't change, we'd suddenly change the page to-be-mapped. Link: https://lkml.kernel.org/r/6a8f2110-fa91-4c10-9eae-88315309a6e3@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx> Closes: https://lore.kernel.org/oe-lkp/202312192319.fa8f5709-oliver.sang@xxxxxxxxx Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/memory.c~mm-convert-ksm_might_need_to_copy-to-work-on-folios-fix-fix +++ a/mm/memory.c @@ -3952,7 +3952,8 @@ vm_fault_t do_swap_page(struct vm_fault folio = swapcache; goto out_page; } - page = folio_page(folio, 0); + if (folio != swapcache) + page = folio_page(folio, 0); /* * If we want to map a page that's in the swapcache writable, we _ Patches currently in -mm which might be from david@xxxxxxxxxx are mm-convert-ksm_might_need_to_copy-to-work-on-folios-fix-fix.patch mm-rmap-rename-hugepage_add-to-hugetlb_add.patch mm-rmap-introduce-and-use-hugetlb_remove_rmap.patch mm-rmap-introduce-and-use-hugetlb_add_file_rmap.patch mm-rmap-introduce-and-use-hugetlb_try_dup_anon_rmap.patch mm-rmap-introduce-and-use-hugetlb_try_share_anon_rmap.patch mm-rmap-add-hugetlb-sanity-checks-for-anon-rmap-handling.patch mm-rmap-convert-folio_add_file_rmap_range-into-folio_add_file_rmap_.patch mm-memory-page_add_file_rmap-folio_add_file_rmap_.patch mm-huge_memory-page_add_file_rmap-folio_add_file_rmap_pmd.patch mm-migrate-page_add_file_rmap-folio_add_file_rmap_pte.patch mm-userfaultfd-page_add_file_rmap-folio_add_file_rmap_pte.patch mm-rmap-remove-page_add_file_rmap.patch mm-rmap-factor-out-adding-folio-mappings-into-__folio_add_rmap.patch mm-rmap-introduce-folio_add_anon_rmap_.patch mm-huge_memory-batch-rmap-operations-in-__split_huge_pmd_locked.patch mm-huge_memory-page_add_anon_rmap-folio_add_anon_rmap_pmd.patch mm-migrate-page_add_anon_rmap-folio_add_anon_rmap_pte.patch mm-ksm-page_add_anon_rmap-folio_add_anon_rmap_pte.patch mm-swapfile-page_add_anon_rmap-folio_add_anon_rmap_pte.patch mm-memory-page_add_anon_rmap-folio_add_anon_rmap_pte.patch mm-rmap-remove-page_add_anon_rmap.patch mm-rmap-remove-rmap_compound.patch mm-rmap-introduce-folio_remove_rmap_.patch kernel-events-uprobes-page_remove_rmap-folio_remove_rmap_pte.patch mm-huge_memory-page_remove_rmap-folio_remove_rmap_pmd.patch mm-khugepaged-page_remove_rmap-folio_remove_rmap_pte.patch mm-ksm-page_remove_rmap-folio_remove_rmap_pte.patch mm-memory-page_remove_rmap-folio_remove_rmap_pte.patch mm-migrate_device-page_remove_rmap-folio_remove_rmap_pte.patch mm-rmap-page_remove_rmap-folio_remove_rmap_pte.patch documentation-stop-referring-to-page_remove_rmap.patch mm-rmap-remove-page_remove_rmap.patch mm-rmap-convert-page_dup_file_rmap-to-folio_dup_file_rmap_.patch mm-rmap-introduce-folio_try_dup_anon_rmap_.patch mm-huge_memory-page_try_dup_anon_rmap-folio_try_dup_anon_rmap_pmd.patch mm-memory-page_try_dup_anon_rmap-folio_try_dup_anon_rmap_pte.patch mm-rmap-remove-page_try_dup_anon_rmap.patch mm-convert-page_try_share_anon_rmap-to-folio_try_share_anon_rmap_.patch mm-rmap-rename-compound_mapped-to-entirely_mapped.patch mm-remove-one-last-reference-to-page_add__rmap.patch