The patch titled
Subject: arm64/mm: enable ARCH_SUPPORTS_PAGE_TABLE_CHECK
has been added to the -mm mm-unstable branch. Its filename is
arm64-mm-enable-arch_supports_page_table_check.patch
This patch should soon appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Subject: arm64/mm: enable ARCH_SUPPORTS_PAGE_TABLE_CHECK
As commit d283d422c6c4 ("x86: mm: add x86_64 support for page table
check") , enable ARCH_SUPPORTS_PAGE_TABLE_CHECK on arm64.
Add additional page table check stubs for page table helpers, these stubs
can be used to check the existing page table entries.
Link: https://lkml.kernel.org/r/20220507110114.4128854-6-tongtiangen@xxxxxxxxxx
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Signed-off-by: Tong Tiangen <tongtiangen@xxxxxxxxxx>
Reviewed-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/arm64/Kconfig | 1
arch/arm64/include/asm/pgtable.h | 61 ++++++++++++++++++++++++++---
2 files changed, 56 insertions(+), 6 deletions(-)
--- a/arch/arm64/include/asm/pgtable.h~arm64-mm-enable-arch_supports_page_table_check
+++ a/arch/arm64/include/asm/pgtable.h
@@ -33,6 +33,7 @@
#include <linux/mmdebug.h>
#include <linux/mm_types.h>
#include <linux/sched.h>
+#include <linux/page_table_check.h>
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
#define __HAVE_ARCH_FLUSH_PMD_TLB_RANGE
@@ -96,6 +97,7 @@ static inline pteval_t __phys_to_pte_val
#define pte_young(pte) (!!(pte_val(pte) & PTE_AF))
#define pte_special(pte) (!!(pte_val(pte) & PTE_SPECIAL))
#define pte_write(pte) (!!(pte_val(pte) & PTE_WRITE))
+#define pte_user(pte) (!!(pte_val(pte) & PTE_USER))
#define pte_user_exec(pte) (!(pte_val(pte) & PTE_UXN))
#define pte_cont(pte) (!!(pte_val(pte) & PTE_CONT))
#define pte_devmap(pte) (!!(pte_val(pte) & PTE_DEVMAP))
@@ -312,8 +314,8 @@ static inline void __check_racy_pte_upda
__func__, pte_val(old_pte), pte_val(pte));
}
-static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pte)
+static inline void __set_pte_at(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte)
{
if (pte_present(pte) && pte_user_exec(pte) && !pte_special(pte))
__sync_icache_dcache(pte);
@@ -343,6 +345,13 @@ static inline void set_pte_at(struct mm_
set_pte(ptep, pte);
}
+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);
+ return __set_pte_at(mm, addr, ptep, pte);
+}
+
/*
* Huge pte definitions.
*/
@@ -454,6 +463,8 @@ static inline int pmd_trans_huge(pmd_t p
#define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd))
#define pmd_young(pmd) pte_young(pmd_pte(pmd))
#define pmd_valid(pmd) pte_valid(pmd_pte(pmd))
+#define pmd_user(pmd) pte_user(pmd_pte(pmd))
+#define pmd_user_exec(pmd) pte_user_exec(pmd_pte(pmd))
#define pmd_cont(pmd) pte_cont(pmd_pte(pmd))
#define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd)))
#define pmd_mkold(pmd) pte_pmd(pte_mkold(pmd_pte(pmd)))
@@ -501,8 +512,19 @@ static inline pmd_t pmd_mkdevmap(pmd_t p
#define pud_pfn(pud) ((__pud_to_phys(pud) & PUD_MASK) >> PAGE_SHIFT)
#define pfn_pud(pfn,prot) __pud(__phys_to_pud_val((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
-#define set_pmd_at(mm, addr, pmdp, pmd) set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(pmd))
-#define set_pud_at(mm, addr, pudp, pud) set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud))
+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);
+ return __set_pte_at(mm, addr, (pte_t *)pmdp, pmd_pte(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);
+ return __set_pte_at(mm, addr, (pte_t *)pudp, pud_pte(pud));
+}
#define __p4d_to_phys(p4d) __pte_to_phys(p4d_pte(p4d))
#define __phys_to_p4d_val(phys) __phys_to_pte_val(phys)
@@ -643,6 +665,24 @@ static inline unsigned long pmd_page_vad
#define pud_present(pud) pte_present(pud_pte(pud))
#define pud_leaf(pud) (pud_present(pud) && !pud_table(pud))
#define pud_valid(pud) pte_valid(pud_pte(pud))
+#define pud_user(pud) pte_user(pud_pte(pud))
+
+#ifdef CONFIG_PAGE_TABLE_CHECK
+static inline bool pte_user_accessible_page(pte_t pte)
+{
+ return pte_present(pte) && (pte_user(pte) || pte_user_exec(pte));
+}
+
+static inline bool pmd_user_accessible_page(pmd_t pmd)
+{
+ return pmd_present(pmd) && (pmd_user(pmd) || pmd_user_exec(pmd));
+}
+
+static inline bool pud_user_accessible_page(pud_t pud)
+{
+ return pud_present(pud) && pud_user(pud);
+}
+#endif
static inline void set_pud(pud_t *pudp, pud_t pud)
{
@@ -876,7 +916,11 @@ static inline int pmdp_test_and_clear_yo
static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
unsigned long address, pte_t *ptep)
{
- return __pte(xchg_relaxed(&pte_val(*ptep), 0));
+ pte_t pte = __pte(xchg_relaxed(&pte_val(*ptep), 0));
+
+ page_table_check_pte_clear(mm, address, pte);
+
+ return pte;
}
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -884,7 +928,11 @@ static inline pte_t ptep_get_and_clear(s
static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
unsigned long address, pmd_t *pmdp)
{
- return pte_pmd(ptep_get_and_clear(mm, address, (pte_t *)pmdp));
+ pmd_t pmd = __pmd(xchg_relaxed(&pmd_val(*pmdp), 0));
+
+ page_table_check_pmd_clear(mm, address, pmd);
+
+ return pmd;
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
@@ -918,6 +966,7 @@ static inline void pmdp_set_wrprotect(st
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);
return __pmd(xchg_relaxed(&pmd_val(*pmdp), pmd_val(pmd)));
}
#endif
--- a/arch/arm64/Kconfig~arm64-mm-enable-arch_supports_page_table_check
+++ a/arch/arm64/Kconfig
@@ -92,6 +92,7 @@ config ARM64
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
select ARCH_SUPPORTS_NUMA_BALANCING
+ select ARCH_SUPPORTS_PAGE_TABLE_CHECK
select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
select ARCH_WANT_DEFAULT_BPF_JIT
select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
_
Patches currently in -mm which might be from wangkefeng.wang@xxxxxxxxxx are
mm-page_table_check-move-pxx_user_accessible_page-into-x86.patch
arm64-mm-enable-arch_supports_page_table_check.patch
