[PATCH v18 08/12] mm/page_table_check: Reinstate address parameter in [__]page_table_check_pte_clear()

Andrew Donnellan
2025-12-18T17:11:21Z

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

This reverts commit aa232204c468 ("mm/page_table_check: remove unused
parameter in [__]page_table_check_pte_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, fix additional occurrence and loop handling]
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>
---
v13: fix an additional occurrence
v15: rebase, fix loop handling
---
arch/arm64/include/asm/pgtable.h | 2 +-
arch/riscv/include/asm/pgtable.h | 2 +-
arch/x86/include/asm/pgtable.h | 4 ++--
include/linux/page_table_check.h | 11 +++++++----
include/linux/pgtable.h | 4 ++--
mm/page_table_check.c | 7 ++++---
6 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 5abad90913eb8b0a3aa867cd5a66107bbf96e177..ce64c560e284e1c2ff9d698cf868070ed58ba045 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -1342,7 +1342,7 @@ static inline pte_t __ptep_get_and_clear_anysz(struct mm_struct *mm,

switch (pgsize) {
case PAGE_SIZE:
- page_table_check_pte_clear(mm, pte);
+ page_table_check_pte_clear(mm, address, pte);
break;
case PMD_SIZE:
page_table_check_pmd_clear(mm, address, pte_pmd(pte));
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index f179970fe47d333565a9199e0991e806aed44346..9af5bfc780800fe2f974daa5329277c46877f848 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -662,7 +662,7 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
{
pte_t pte = __pte(atomic_long_xchg((atomic_long_t *)ptep, 0));

- page_table_check_pte_clear(mm, pte);
+ page_table_check_pte_clear(mm, address, pte);

return pte;
}
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 5a2b2d3a80d83d8eff2c1a6f69df3e80590c684a..6ec6cf7ad2d4d92da7d3396bc96a5b5902e81576 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1252,7 +1252,7 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
pte_t pte = native_ptep_get_and_clear(ptep);
- page_table_check_pte_clear(mm, pte);
+ page_table_check_pte_clear(mm, addr, pte);
return pte;
}

@@ -1268,7 +1268,7 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
* care about updates and native needs no locking
*/
pte = native_local_ptep_get_and_clear(ptep);
- page_table_check_pte_clear(mm, pte);
+ page_table_check_pte_clear(mm, addr, pte);
} else {
pte = ptep_get_and_clear(mm, addr, ptep);
}
diff --git a/include/linux/page_table_check.h b/include/linux/page_table_check.h
index 3973b69ae294e501a9c6c3140bc462d6d9b7d203..12268a32e8be151f66f2787ce87096f10d4fa744 100644
--- a/include/linux/page_table_check.h
+++ b/include/linux/page_table_check.h
@@ -14,7 +14,8 @@ extern struct static_key_true page_table_check_disabled;
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_pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t pte);
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,
@@ -45,12 +46,13 @@ static inline void page_table_check_free(struct page *page, unsigned int order)
__page_table_check_zero(page, order);
}

-static inline void page_table_check_pte_clear(struct mm_struct *mm, pte_t pte)
+static inline void page_table_check_pte_clear(struct mm_struct *mm,
+ unsigned long addr, pte_t pte)
{
if (static_branch_likely(&page_table_check_disabled))
return;

- __page_table_check_pte_clear(mm, pte);
+ __page_table_check_pte_clear(mm, addr, pte);
}

static inline void page_table_check_pmd_clear(struct mm_struct *mm,
@@ -119,7 +121,8 @@ static inline void page_table_check_free(struct page *page, unsigned int order)
{
}

-static inline void page_table_check_pte_clear(struct mm_struct *mm, pte_t pte)
+static inline void page_table_check_pte_clear(struct mm_struct *mm,
+ unsigned long addr, pte_t pte)
{
}

diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index 2d1f7369624c504b531beb8965e7352770a5f4bc..827dca25c0bc77025653f31075ed6913355bda08 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -634,7 +634,7 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
{
pte_t pte = ptep_get(ptep);
pte_clear(mm, address, ptep);
- page_table_check_pte_clear(mm, pte);
+ page_table_check_pte_clear(mm, address, pte);
return pte;
}
#endif
@@ -693,7 +693,7 @@ static inline void ptep_clear(struct mm_struct *mm, unsigned long addr,
* No need for ptep_get_and_clear(): page table check doesn't care about
* any bits that could have been set by HW concurrently.
*/
- page_table_check_pte_clear(mm, pte);
+ page_table_check_pte_clear(mm, addr, pte);
}

#ifdef CONFIG_GUP_GET_PXX_LOW_HIGH
diff --git a/mm/page_table_check.c b/mm/page_table_check.c
index e8280b0b6dda97ee68bb52593df454665bac9acf..de9e54bd27e6f2bce68304a0b3e99b139f33c313 100644
--- a/mm/page_table_check.c
+++ b/mm/page_table_check.c
@@ -145,7 +145,8 @@ void __page_table_check_zero(struct page *page, unsigned int order)
rcu_read_unlock();
}

-void __page_table_check_pte_clear(struct mm_struct *mm, pte_t pte)
+void __page_table_check_pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t pte)
{
if (&init_mm == mm)
return;
@@ -209,7 +210,7 @@ void __page_table_check_ptes_set(struct mm_struct *mm, unsigned long addr,
page_table_check_pte_flags(pte);

for (i = 0; i < nr; i++)
- __page_table_check_pte_clear(mm, ptep_get(ptep + i));
+ __page_table_check_pte_clear(mm, addr + PAGE_SIZE * i, ptep_get(ptep + i));
if (pte_user_accessible_page(pte))
page_table_check_set(pte_pfn(pte), nr, pte_write(pte));
}
@@ -275,7 +276,7 @@ void __page_table_check_pte_clear_range(struct mm_struct *mm,
if (WARN_ON(!ptep))
return;
for (i = 0; i < PTRS_PER_PTE; i++) {
- __page_table_check_pte_clear(mm, ptep_get(ptep));
+ __page_table_check_pte_clear(mm, addr, ptep_get(ptep));
addr += PAGE_SIZE;
ptep++;
}

--
2.52.0