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

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

[Andrew Morton]

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

This patch should soon appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

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

Patch series "mm: page_table_check: add support on arm64 and riscv", v7.

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 6):

Compared with PxD_PAGE_SIZE, which is defined and used only on X86,
PxD_SIZE is more common in each architecture.  Therefore, it is more
reasonable to use PxD_SIZE instead of PxD_PAGE_SIZE in page_table_check.c.
At the same time, it is easier to support page table check in other
architectures.  The substitution has no functional impact on the x86.

Link: https://lkml.kernel.org/r/20220507110114.4128854-1-tongtiangen@huawei.com
Link: https://lkml.kernel.org/r/20220507110114.4128854-2-tongtiangen@huawei.com
Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
Suggested-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
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: Kefeng Wang <wangkefeng.wang@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
mm-remove-__have_arch_ptep_clear-in-pgtableh.patch
riscv-mm-enable-arch_supports_page_table_check.patch