The quilt patch titled Subject: mm: clarify folio_set_compound_order() zero support has been removed from the -mm tree. Its filename was mm-add-folio-dtor-and-order-setter-functions-fix.patch This patch was dropped because it was folded into mm-add-folio-dtor-and-order-setter-functions.patch ------------------------------------------------------ From: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> Subject: mm: clarify folio_set_compound_order() zero support Date: Wed, 7 Dec 2022 14:37:31 -0800 Document hugetlb's use of a zero compound order so support for zero orders is not removed from folio_set_compound_order(). Link: https://lkml.kernel.org/r/20221207223731.32784-1-sidhartha.kumar@xxxxxxxxxx Signed-off-by: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> Suggested-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Suggested-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/mm.h | 7 +++++++ 1 file changed, 7 insertions(+) --- a/include/linux/mm.h~mm-add-folio-dtor-and-order-setter-functions-fix +++ a/include/linux/mm.h @@ -1019,9 +1019,16 @@ static inline void set_compound_order(st #endif } +/* + * folio_set_compound_order is generally passed a non-zero order to + * initialize a large folio. However, hugetlb code abuses this by + * passing in zero when 'dissolving' a large folio. + */ static inline void folio_set_compound_order(struct folio *folio, unsigned int order) { + VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); + folio->_folio_order = order; #ifdef CONFIG_64BIT folio->_folio_nr_pages = order ? 1U << order : 0; _ Patches currently in -mm which might be from sidhartha.kumar@xxxxxxxxxx are mm-add-folio-dtor-and-order-setter-functions.patch mm-hugetlb-convert-destroy_compound_gigantic_page-to-folios.patch mm-hugetlb-convert-dissolve_free_huge_page-to-folios.patch mm-hugetlb-convert-remove_hugetlb_page-to-folios.patch mm-hugetlb-convert-update_and_free_page-to-folios.patch mm-hugetlb-convert-add_hugetlb_page-to-folios-and-add-hugetlb_cma_folio.patch mm-hugetlb-convert-enqueue_huge_page-to-folios.patch mm-hugetlb-convert-free_gigantic_page-to-folios.patch mm-hugetlb-convert-hugetlb-prep-functions-to-folios.patch mm-hugetlb-change-hugetlb-allocation-functions-to-return-a-folio.patch mm-hugetlb-change-hugetlb-allocation-functions-to-return-a-folio-fix.patch