diff --git a/mm/page_table_check.c b/mm/page_table_check.c index 53a8997ec043..2403f5a11410 100644 --- a/mm/page_table_check.c +++ b/mm/page_table_check.c @@ -151,18 +151,29 @@ void __page_table_check_pte_clear(struct mm_struct *mm, unsigned long addr, if (&init_mm == mm) return; - if (pte_user_accessible_page(mm, addr, pte)) + if (pte_user_accessible_page(mm, addr, pte) && !pte_special(pte)) page_table_check_clear(pte_pfn(pte), PAGE_SIZE >> PAGE_SHIFT); } EXPORT_SYMBOL(__page_table_check_pte_clear); +static inline bool page_table_check_huge_zero_pmd(pmd_t pmd) +{ + unsigned long pfn = pmd_pfn(pmd); + + if (!pfn_valid(pfn)) + return false; + + return is_huge_zero_folio(page_folio(pfn_to_page(pfn))); +} + void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr, pmd_t pmd) { if (&init_mm == mm) return; - if (pmd_user_accessible_page(mm, addr, pmd)) + if (pmd_user_accessible_page(mm, addr, pmd) && + !page_table_check_huge_zero_pmd(pmd)) page_table_check_clear(pmd_pfn(pmd), PMD_SIZE >> PAGE_SHIFT); } EXPORT_SYMBOL(__page_table_check_pmd_clear); @@ -208,7 +219,7 @@ void __page_table_check_ptes_set(struct mm_struct *mm, unsigned long addr, for (i = 0; i < nr; i++) __page_table_check_pte_clear(mm, addr + PAGE_SIZE * i, ptep_get(ptep + i)); - if (pte_user_accessible_page(mm, addr, pte)) + if (pte_user_accessible_page(mm, addr, pte) && !pte_special(pte)) page_table_check_set(pte_pfn(pte), nr, pte_write(pte)); } EXPORT_SYMBOL(__page_table_check_ptes_set); @@ -238,7 +249,8 @@ void __page_table_check_pmds_set(struct mm_struct *mm, unsigned long addr, for (i = 0; i < nr; i++) __page_table_check_pmd_clear(mm, addr + PMD_SIZE * i, *(pmdp + i)); - if (pmd_user_accessible_page(mm, addr, pmd)) + if (pmd_user_accessible_page(mm, addr, pmd) && + !page_table_check_huge_zero_pmd(pmd)) page_table_check_set(pmd_pfn(pmd), stride * nr, pmd_write(pmd)); } EXPORT_SYMBOL(__page_table_check_pmds_set);