linux-kernel - [PATCH 1/5] arm64/mm: Drop pte

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20241005123824.1366397-2-anshuman.khandual@arm.com>
Date: Sat,  5 Oct 2024 18:08:20 +0530
From: Anshuman Khandual <anshuman.khandual@....com>
To: linux-arm-kernel@...ts.infradead.org
Cc: Anshuman Khandual <anshuman.khandual@....com>,
	Marc Zyngier <maz@...nel.org>,
	Oliver Upton <oliver.upton@...ux.dev>,
	James Morse <james.morse@....com>,
	Catalin Marinas <catalin.marinas@....com>,
	Will Deacon <will@...nel.org>,
	Ard Biesheuvel <ardb@...nel.org>,
	Ryan Roberts <ryan.roberts@....com>,
	Mark Rutland <mark.rutland@....com>,
	kvmarm@...ts.linux.dev,
	linux-kernel@...r.kernel.org
Subject: [PATCH 1/5] arm64/mm: Drop pte_mkhuge()

Core HugeTLB defines arch_make_huge_pte() fallback definition, which calls
platform provided pte_mkhuge(). But if any platform already provides custom
arch_make_huge_pte(), then it does not need to provide pte_mkhuge(). arm64
defines arch_make_huge_pte(), but then also calls pte_mkhuge() internally.
This creates confusion as if both of these callbacks are being used in core
HugeTLB and required to be defined in the platform.

This changes arch_make_huge_pte() to create block mapping directly and also
drops off now redundant helper pte_mkhuge(), making things clear. Also this
changes HugeTLB page creation from just clearing the PTE_TABLE_BIT (bit[1])
to actually setting bits[1:0] via PTE_TYPE_[MASK|SECT] instead.

Cc: Catalin Marinas <catalin.marinas@....com>
Cc: Will Deacon <will@...nel.org>
Cc: Ard Biesheuvel <ardb@...nel.org>
Cc: Ryan Roberts <ryan.roberts@....com>
Cc: Mark Rutland <mark.rutland@....com>
Cc: linux-arm-kernel@...ts.infradead.org
Cc: linux-kernel@...r.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@....com>
---
 arch/arm64/include/asm/pgtable-hwdef.h | 1 +
 arch/arm64/include/asm/pgtable.h       | 5 -----
 arch/arm64/mm/hugetlbpage.c            | 2 +-
 3 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h
index fd330c1db289..956a702cb532 100644
--- a/arch/arm64/include/asm/pgtable-hwdef.h
+++ b/arch/arm64/include/asm/pgtable-hwdef.h
@@ -158,6 +158,7 @@
 #define PTE_VALID		(_AT(pteval_t, 1) << 0)
 #define PTE_TYPE_MASK		(_AT(pteval_t, 3) << 0)
 #define PTE_TYPE_PAGE		(_AT(pteval_t, 3) << 0)
+#define PTE_TYPE_SECT		(_AT(pteval_t, 1) << 0)
 #define PTE_TABLE_BIT		(_AT(pteval_t, 1) << 1)
 #define PTE_USER		(_AT(pteval_t, 1) << 6)		/* AP[1] */
 #define PTE_RDONLY		(_AT(pteval_t, 1) << 7)		/* AP[2] */
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index c329ea061dc9..fa4c32a9f572 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -438,11 +438,6 @@ static inline void __set_ptes(struct mm_struct *mm,
 	}
 }
 
-/*
- * Huge pte definitions.
- */
-#define pte_mkhuge(pte)		(__pte(pte_val(pte) & ~PTE_TABLE_BIT))
-
 /*
  * Hugetlb definitions.
  */
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 5f1e2103888b..5922c95630ad 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -361,7 +361,7 @@ pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags)
 {
 	size_t pagesize = 1UL << shift;
 
-	entry = pte_mkhuge(entry);
+	entry = __pte((pte_val(entry) & ~PTE_TYPE_MASK) | PTE_TYPE_SECT);
 	if (pagesize == CONT_PTE_SIZE) {
 		entry = pte_mkcont(entry);
 	} else if (pagesize == CONT_PMD_SIZE) {
-- 
2.25.1