[PATCH v15 07/13] mm/page_table_check: Reinstate address parameter in [__]page_table_check_pmd_clear()

From: Andrew Donnellan <ajd@linux.ibm.com>
To: linuxppc-dev@lists.ozlabs.org, pasha.tatashin@soleen.com,
	akpm@linux-foundation.org
Cc: linux-kernel@vger.kernel.org, x86@kernel.org,
	linux-riscv@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org,
	sweettea-kernel@dorminy.me, christophe.leroy@csgroup.eu,
	mingo@kernel.org
Subject: [PATCH v15 07/13] mm/page_table_check: Reinstate address parameter in [__]page_table_check_pmd_clear()
Date: Wed, 25 Jun 2025 16:37:47 +1000	[thread overview]
Message-ID: <20250625063753.77511-8-ajd@linux.ibm.com> (raw)
In-Reply-To: <20250625063753.77511-1-ajd@linux.ibm.com>

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
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 72ccbd810b13..db8bab350a2d 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -1394,7 +1394,7 @@ 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 7b292af35f4b..cc3c690f6c93 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -877,7 +877,7 @@ 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 4d6da32e77a6..50d76a38ab9f 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1365,7 +1365,7 @@ 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 808cc3a48c28..3973b69ae294 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 765451864de3..13e9336bf20e 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -637,7 +637,7 @@ 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 bd1242087a35..e8c26b616aed 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;
@@ -231,7 +232,7 @@ 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));
 }
-- 
2.49.0


