+ mm-page_table_check-using-pxd_size-instead-of-pxd_page_size.patch added to -mm tree

+ mm-page_table_check-using-pxd_size-instead-of-pxd_page_size.patch added to -mm tree

[Andrew Morton]

The patch titled
     Subject: mm: page_table_check: use PxD_SIZE instead of PxD_PAGE_SIZE
has been added to the -mm tree.  Its filename is
     mm-page_table_check-using-pxd_size-instead-of-pxd_page_size.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-page_table_check-using-pxd_size-instead-of-pxd_page_size.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-page_table_check-using-pxd_size-instead-of-pxd_page_size.patch

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------------------------------------------------------
From: Tong Tiangen <tongtiangen@huawei.com>
Subject: mm: page_table_check: use PxD_SIZE instead of PxD_PAGE_SIZE

Patch series "mm: page_table_check: add support on arm64 and riscv", v5.

Page table check performs extra verifications at the time when new pages
become accessible from the userspace by getting their page table entries
(PTEs PMDs etc.) added into the table.  It is supported on X86[1].

This patchset made some simple changes and make it easier to support new
architecture, then we support this feature on ARM64 and RISCV.

[1]https://lore.kernel.org/lkml/20211123214814.3756047-1-pasha.tatashin@soleen.com/


This patch (of 5):

Macro PUD_SIZE/PMD_SIZE is more general in various architectures.  Using
PUD_SIZE/PMD_SIZE instead of PUD_PAGE_SIZE/PMD_PAGE_SIZE can better
support page table check in architectures other than x86 and it is no
functional impact on x86.

Link: https://lkml.kernel.org/r/20220421082042.1167967-1-tongtiangen@huawei.com
Link: https://lkml.kernel.org/r/20220421082042.1167967-2-tongtiangen@huawei.com
Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
Suggested-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Guohanjun <guohanjun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/page_table_check.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/mm/page_table_check.c~mm-page_table_check-using-pxd_size-instead-of-pxd_page_size
+++ a/mm/page_table_check.c
@@ -177,7 +177,7 @@ void __page_table_check_pmd_clear(struct
 
 	if (pmd_user_accessible_page(pmd)) {
 		page_table_check_clear(mm, addr, pmd_pfn(pmd),
-				       PMD_PAGE_SIZE >> PAGE_SHIFT);
+				       PMD_SIZE >> PAGE_SHIFT);
 	}
 }
 EXPORT_SYMBOL(__page_table_check_pmd_clear);
@@ -190,7 +190,7 @@ void __page_table_check_pud_clear(struct
 
 	if (pud_user_accessible_page(pud)) {
 		page_table_check_clear(mm, addr, pud_pfn(pud),
-				       PUD_PAGE_SIZE >> PAGE_SHIFT);
+				       PUD_SIZE >> PAGE_SHIFT);
 	}
 }
 EXPORT_SYMBOL(__page_table_check_pud_clear);
@@ -219,7 +219,7 @@ void __page_table_check_pmd_set(struct m
 	__page_table_check_pmd_clear(mm, addr, *pmdp);
 	if (pmd_user_accessible_page(pmd)) {
 		page_table_check_set(mm, addr, pmd_pfn(pmd),
-				     PMD_PAGE_SIZE >> PAGE_SHIFT,
+				     PMD_SIZE >> PAGE_SHIFT,
 				     pmd_write(pmd));
 	}
 }
@@ -234,7 +234,7 @@ void __page_table_check_pud_set(struct m
 	__page_table_check_pud_clear(mm, addr, *pudp);
 	if (pud_user_accessible_page(pud)) {
 		page_table_check_set(mm, addr, pud_pfn(pud),
-				     PUD_PAGE_SIZE >> PAGE_SHIFT,
+				     PUD_SIZE >> PAGE_SHIFT,
 				     pud_write(pud));
 	}
 }
_

Patches currently in -mm which might be from tongtiangen@huawei.com are

mm-page_table_check-using-pxd_size-instead-of-pxd_page_size.patch
mm-page_table_check-add-hooks-to-public-helpers.patch
riscv-mm-add-support-for-page-table-check.patch