[PATCH v18 07/12] mm/page_table_check: Reinstate address parameter in [__]page_table_check_pmd_clear()

Andrew Donnellan
2025-12-18T17:11:12Z

From: Rohan McLure <rmclure@linux.ibm.com>

This reverts commit 1831414cd729 ("mm/page_table_check: remove unused
parameter in [__]page_table_check_pmd_clear").

Reinstate previously unused parameters for the purpose of supporting
powerpc platforms, as many do not encode user/kernel ownership of the
page in the pte, but instead in the address of the access.

[ajd@linux.ibm.com: rebase on arm64 changes]
Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Acked-by: Ingo Molnar <mingo@kernel.org> # x86
Acked-by: Alexandre Ghiti <alexghiti@rivosinc.com> # riscv
Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
---
v15: rebase
---
arch/arm64/include/asm/pgtable.h | 2 +-
arch/riscv/include/asm/pgtable.h | 2 +-
arch/x86/include/asm/pgtable.h | 2 +-
include/linux/page_table_check.h | 11 +++++++----
include/linux/pgtable.h | 2 +-
mm/page_table_check.c | 5 +++--
6 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 595405e6bfc736f2824a9c2e8784351f15ad0571..5abad90913eb8b0a3aa867cd5a66107bbf96e177 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -1345,7 +1345,7 @@ static inline pte_t __ptep_get_and_clear_anysz(struct mm_struct *mm,
page_table_check_pte_clear(mm, pte);
break;
case PMD_SIZE:
- page_table_check_pmd_clear(mm, pte_pmd(pte));
+ page_table_check_pmd_clear(mm, address, pte_pmd(pte));
break;
#ifndef __PAGETABLE_PMD_FOLDED
case PUD_SIZE:
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 841494ef46ee6ae1410f420dc7d0a99c4e1958cf..f179970fe47d333565a9199e0991e806aed44346 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -999,7 +999,7 @@ static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
{
pmd_t pmd = __pmd(atomic_long_xchg((atomic_long_t *)pmdp, 0));

- page_table_check_pmd_clear(mm, pmd);
+ page_table_check_pmd_clear(mm, address, pmd);

return pmd;
}
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 3eb36a36058face6aba92efe3eed7214752e751f..5a2b2d3a80d83d8eff2c1a6f69df3e80590c684a 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1319,7 +1319,7 @@ static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm, unsigned long
{
pmd_t pmd = native_pmdp_get_and_clear(pmdp);

- page_table_check_pmd_clear(mm, pmd);
+ page_table_check_pmd_clear(mm, addr, pmd);

return pmd;
}
diff --git a/include/linux/page_table_check.h b/include/linux/page_table_check.h
index 808cc3a48c28fcf988ba2c50031fa4f317496582..3973b69ae294e501a9c6c3140bc462d6d9b7d203 100644
--- a/include/linux/page_table_check.h
+++ b/include/linux/page_table_check.h
@@ -15,7 +15,8 @@ extern struct page_ext_operations page_table_check_ops;

void __page_table_check_zero(struct page *page, unsigned int order);
void __page_table_check_pte_clear(struct mm_struct *mm, pte_t pte);
-void __page_table_check_pmd_clear(struct mm_struct *mm, pmd_t pmd);
+void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr,
+ pmd_t pmd);
void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr,
pud_t pud);
void __page_table_check_ptes_set(struct mm_struct *mm, unsigned long addr,
@@ -52,12 +53,13 @@ static inline void page_table_check_pte_clear(struct mm_struct *mm, pte_t pte)
__page_table_check_pte_clear(mm, pte);
}

-static inline void page_table_check_pmd_clear(struct mm_struct *mm, pmd_t pmd)
+static inline void page_table_check_pmd_clear(struct mm_struct *mm,
+ unsigned long addr, pmd_t pmd)
{
if (static_branch_likely(&page_table_check_disabled))
return;

- __page_table_check_pmd_clear(mm, pmd);
+ __page_table_check_pmd_clear(mm, addr, pmd);
}

static inline void page_table_check_pud_clear(struct mm_struct *mm,
@@ -121,7 +123,8 @@ static inline void page_table_check_pte_clear(struct mm_struct *mm, pte_t pte)
{
}

-static inline void page_table_check_pmd_clear(struct mm_struct *mm, pmd_t pmd)
+static inline void page_table_check_pmd_clear(struct mm_struct *mm,
+ unsigned long addr, pmd_t pmd)
{
}

diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index ed3c28ebeb35b766418abdefa5cc6604c0533479..2d1f7369624c504b531beb8965e7352770a5f4bc 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -788,7 +788,7 @@ static inline pmd_t pmdp_huge_get_and_clear(struct mm_struct *mm,
pmd_t pmd = *pmdp;

pmd_clear(pmdp);
- page_table_check_pmd_clear(mm, pmd);
+ page_table_check_pmd_clear(mm, address, pmd);

return pmd;
}
diff --git a/mm/page_table_check.c b/mm/page_table_check.c
index 2295bc9368ab9cc827ee671ff9abf18a6b738172..e8280b0b6dda97ee68bb52593df454665bac9acf 100644
--- a/mm/page_table_check.c
+++ b/mm/page_table_check.c
@@ -156,7 +156,8 @@ void __page_table_check_pte_clear(struct mm_struct *mm, pte_t pte)
}
EXPORT_SYMBOL(__page_table_check_pte_clear);

-void __page_table_check_pmd_clear(struct mm_struct *mm, pmd_t pmd)
+void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr,
+ pmd_t pmd)
{
if (&init_mm == mm)
return;
@@ -238,7 +239,7 @@ void __page_table_check_pmds_set(struct mm_struct *mm, unsigned long addr,
page_table_check_pmd_flags(pmd);

for (i = 0; i < nr; i++)
- __page_table_check_pmd_clear(mm, *(pmdp + i));
+ __page_table_check_pmd_clear(mm, addr + PMD_SIZE * i, *(pmdp + i));
if (pmd_user_accessible_page(pmd))
page_table_check_set(pmd_pfn(pmd), stride * nr, pmd_write(pmd));
}

--
2.52.0