[PATCH 5.10 32/86] arm64/mm: Remove [PUD|PMD]_TABLE_BIT from [pud|pmd]_bad()

[PATCH 5.10 32/86] arm64/mm: Remove [PUD|PMD]_TABLE_BIT from [pud|pmd]_bad()

[Greg Kroah-Hartman]

From: Anshuman Khandual <anshuman.khandual@arm.com>

[ Upstream commit e377ab82311af95c99648c6424a6b888a0ccb102 ]

Semantics wise, [pud|pmd]_bad() have always implied that a given [PUD|PMD]
entry does not have a pointer to the next level page table. This had been
made clear in the commit a1c76574f345 ("arm64: mm: use *_sect to check for
section maps"). Hence explicitly check for a table entry rather than just
testing a single bit. This basically redefines [pud|pmd]_bad() in terms of
[pud|pmd]_table() making the semantics clear.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/1620644871-26280-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm64/include/asm/pgtable.h | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index f3a70dc7c594..9cf8e304bb56 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -512,13 +512,12 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
 
 #define pmd_none(pmd)		(!pmd_val(pmd))
 
-#define pmd_bad(pmd)		(!(pmd_val(pmd) & PMD_TABLE_BIT))
-
 #define pmd_table(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
 				 PMD_TYPE_TABLE)
 #define pmd_sect(pmd)		((pmd_val(pmd) & PMD_TYPE_MASK) == \
 				 PMD_TYPE_SECT)
 #define pmd_leaf(pmd)		pmd_sect(pmd)
+#define pmd_bad(pmd)		(!pmd_table(pmd))
 
 #if defined(CONFIG_ARM64_64K_PAGES) || CONFIG_PGTABLE_LEVELS < 3
 static inline bool pud_sect(pud_t pud) { return false; }
@@ -602,7 +601,7 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd)
 	pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e))
 
 #define pud_none(pud)		(!pud_val(pud))
-#define pud_bad(pud)		(!(pud_val(pud) & PUD_TABLE_BIT))
+#define pud_bad(pud)		(!pud_table(pud))
 #define pud_present(pud)	pte_present(pud_pte(pud))
 #define pud_leaf(pud)		pud_sect(pud)
 #define pud_valid(pud)		pte_valid(pud_pte(pud))
-- 
2.35.1




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[PATCH 5.10 34/86] ARM: vexpress/spc: Avoid negative array index when !SMP

[Greg Kroah-Hartman]

From: Kees Cook <keescook@chromium.org>

[ Upstream commit b3f1dd52c991d79118f35e6d1bf4d7cb09882e38 ]

When building multi_v7_defconfig+CONFIG_SMP=n, -Warray-bounds exposes
a couple negative array index accesses:

arch/arm/mach-vexpress/spc.c: In function 've_spc_clk_init':
arch/arm/mach-vexpress/spc.c:583:21: warning: array subscript -1 is below array bounds of 'bool[2]' {aka '_Bool[2]'} [-Warray-bounds]
  583 |   if (init_opp_table[cluster])
      |       ~~~~~~~~~~~~~~^~~~~~~~~
arch/arm/mach-vexpress/spc.c:556:7: note: while referencing 'init_opp_table'
  556 |  bool init_opp_table[MAX_CLUSTERS] = { false };
      |       ^~~~~~~~~~~~~~
arch/arm/mach-vexpress/spc.c:592:18: warning: array subscript -1 is below array bounds of 'bool[2]' {aka '_Bool[2]'} [-Warray-bounds]
  592 |    init_opp_table[cluster] = true;
      |    ~~~~~~~~~~~~~~^~~~~~~~~
arch/arm/mach-vexpress/spc.c:556:7: note: while referencing 'init_opp_table'
  556 |  bool init_opp_table[MAX_CLUSTERS] = { false };
      |       ^~~~~~~~~~~~~~

Skip this logic when built !SMP.

Link: https://lore.kernel.org/r/20220331190443.851661-1-keescook@chromium.org
Cc: Liviu Dudau <liviu.dudau@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/mach-vexpress/spc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/mach-vexpress/spc.c b/arch/arm/mach-vexpress/spc.c
index 1da11bdb1dfb..1c6500c4e6a1 100644
--- a/arch/arm/mach-vexpress/spc.c
+++ b/arch/arm/mach-vexpress/spc.c
@@ -580,7 +580,7 @@ static int __init ve_spc_clk_init(void)
 		}
 
 		cluster = topology_physical_package_id(cpu_dev->id);
-		if (init_opp_table[cluster])
+		if (cluster < 0 || init_opp_table[cluster])
 			continue;
 
 		if (ve_init_opp_table(cpu_dev))
-- 
2.35.1




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