The patch titled Subject: x86: mm: add x86_64 support for page table check has been added to the -mm tree. Its filename is x86-mm-add-x86_64-support-for-page-table-check.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/x86-mm-add-x86_64-support-for-page-table-check.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/x86-mm-add-x86_64-support-for-page-table-check.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: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx> Subject: x86: mm: add x86_64 support for page table check Add page table check hooks into routines that modify user page tables. Link: https://lkml.kernel.org/r/20211204182314.1470076-5-pasha.tatashin@xxxxxxxxxx Signed-off-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Frederic Weisbecker <frederic@xxxxxxxxxx> Cc: Greg Thelen <gthelen@xxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jiri Slaby <jirislaby@xxxxxxxxxx> Cc: Jonathan Corbet <corbet@xxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxx> Cc: Muchun Song <songmuchun@xxxxxxxxxxxxx> Cc: Paul Turner <pjt@xxxxxxxxxx> Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Sami Tolvanen <samitolvanen@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Wei Xu <weixugc@xxxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/x86/Kconfig | 1 + arch/x86/include/asm/pgtable.h | 29 +++++++++++++++++++++++++++-- 2 files changed, 28 insertions(+), 2 deletions(-) --- a/arch/x86/include/asm/pgtable.h~x86-mm-add-x86_64-support-for-page-table-check +++ a/arch/x86/include/asm/pgtable.h @@ -26,6 +26,7 @@ #include <asm/pkru.h> #include <asm/fpu/api.h> #include <asm-generic/pgtable_uffd.h> +#include <linux/page_table_check.h> extern pgd_t early_top_pgt[PTRS_PER_PGD]; bool __init __early_make_pgtable(unsigned long address, pmdval_t pmd); @@ -1006,18 +1007,21 @@ static inline pud_t native_local_pudp_ge static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte) { + page_table_check_pte_set(mm, addr, ptep, pte); set_pte(ptep, pte); } static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd) { + page_table_check_pmd_set(mm, addr, pmdp, pmd); set_pmd(pmdp, pmd); } static inline void set_pud_at(struct mm_struct *mm, unsigned long addr, pud_t *pudp, pud_t pud) { + page_table_check_pud_set(mm, addr, pudp, pud); native_set_pud(pudp, pud); } @@ -1048,6 +1052,7 @@ static inline pte_t ptep_get_and_clear(s pte_t *ptep) { pte_t pte = native_ptep_get_and_clear(ptep); + page_table_check_pte_clear(mm, addr, pte); return pte; } @@ -1063,12 +1068,23 @@ static inline pte_t ptep_get_and_clear_f * care about updates and native needs no locking */ pte = native_local_ptep_get_and_clear(ptep); + page_table_check_pte_clear(mm, addr, pte); } else { pte = ptep_get_and_clear(mm, addr, ptep); } return pte; } +#define __HAVE_ARCH_PTEP_CLEAR +static inline void ptep_clear(struct mm_struct *mm, unsigned long addr, + pte_t *ptep) +{ + if (IS_ENABLED(CONFIG_PAGE_TABLE_CHECK)) + ptep_get_and_clear(mm, addr, ptep); + else + pte_clear(mm, addr, ptep); +} + #define __HAVE_ARCH_PTEP_SET_WRPROTECT static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep) @@ -1109,14 +1125,22 @@ static inline int pmd_write(pmd_t pmd) static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp) { - return native_pmdp_get_and_clear(pmdp); + pmd_t pmd = native_pmdp_get_and_clear(pmdp); + + page_table_check_pmd_clear(mm, addr, pmd); + + return pmd; } #define __HAVE_ARCH_PUDP_HUGE_GET_AND_CLEAR static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm, unsigned long addr, pud_t *pudp) { - return native_pudp_get_and_clear(pudp); + pud_t pud = native_pudp_get_and_clear(pudp); + + page_table_check_pud_clear(mm, addr, pud); + + return pud; } #define __HAVE_ARCH_PMDP_SET_WRPROTECT @@ -1137,6 +1161,7 @@ static inline int pud_write(pud_t pud) static inline pmd_t pmdp_establish(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp, pmd_t pmd) { + page_table_check_pmd_set(vma->vm_mm, address, pmdp, pmd); if (IS_ENABLED(CONFIG_SMP)) { return xchg(pmdp, pmd); } else { --- a/arch/x86/Kconfig~x86-mm-add-x86_64-support-for-page-table-check +++ a/arch/x86/Kconfig @@ -104,6 +104,7 @@ config X86 select ARCH_SUPPORTS_ACPI select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_DEBUG_PAGEALLOC + select ARCH_SUPPORTS_PAGE_TABLE_CHECK if X86_64 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP if NR_CPUS <= 4096 select ARCH_SUPPORTS_LTO_CLANG _ Patches currently in -mm which might be from pasha.tatashin@xxxxxxxxxx are mm-change-page-type-prior-to-adding-page-table-entry.patch mm-ptep_clear-page-table-helper.patch mm-page-table-check.patch x86-mm-add-x86_64-support-for-page-table-check.patch