From: Catalin Marinas Date: Thu, 5 May 2016 09:44:02 +0000 (+0100) Subject: arm64: Ensure pmd_present() returns false after pmd_mknotpresent() X-Git-Tag: android-x86-7.1-r1~1526^2~4 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=5bb1cc0ff9a6b68871970737e6c4c16919928d8b;p=android-x86%2Fkernel.git arm64: Ensure pmd_present() returns false after pmd_mknotpresent() Currently, pmd_present() only checks for a non-zero value, returning true even after pmd_mknotpresent() (which only clears the type bits). This patch converts pmd_present() to using pte_present(), similar to the other pmd_*() checks. As a side effect, it will return true for PROT_NONE mappings, though they are not yet used by the kernel with transparent huge pages. For consistency, also change pmd_mknotpresent() to only clear the PMD_SECT_VALID bit, even though the PMD_TABLE_BIT is already 0 for block mappings (no functional change). The unused PMD_SECT_PROT_NONE definition is removed as transparent huge pages use the pte page prot values. Fixes: 9c7e535fcc17 ("arm64: mm: Route pmd thp functions through pte equivalents") Cc: # 3.15+ Reviewed-by: Will Deacon Signed-off-by: Catalin Marinas Signed-off-by: Will Deacon --- diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index 5c25b831273d..9786f770088d 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -133,7 +133,6 @@ * Section */ #define PMD_SECT_VALID (_AT(pmdval_t, 1) << 0) -#define PMD_SECT_PROT_NONE (_AT(pmdval_t, 1) << 58) #define PMD_SECT_USER (_AT(pmdval_t, 1) << 6) /* AP[1] */ #define PMD_SECT_RDONLY (_AT(pmdval_t, 1) << 7) /* AP[2] */ #define PMD_SECT_S (_AT(pmdval_t, 3) << 8) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index b90e4adfcf5e..2da46ae9c991 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -289,6 +289,7 @@ static inline int pmd_protnone(pmd_t pmd) #define pmd_trans_huge(pmd) (pmd_val(pmd) && !(pmd_val(pmd) & PMD_TABLE_BIT)) #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ +#define pmd_present(pmd) pte_present(pmd_pte(pmd)) #define pmd_dirty(pmd) pte_dirty(pmd_pte(pmd)) #define pmd_young(pmd) pte_young(pmd_pte(pmd)) #define pmd_wrprotect(pmd) pte_pmd(pte_wrprotect(pmd_pte(pmd))) @@ -297,7 +298,7 @@ static inline int pmd_protnone(pmd_t pmd) #define pmd_mkclean(pmd) pte_pmd(pte_mkclean(pmd_pte(pmd))) #define pmd_mkdirty(pmd) pte_pmd(pte_mkdirty(pmd_pte(pmd))) #define pmd_mkyoung(pmd) pte_pmd(pte_mkyoung(pmd_pte(pmd))) -#define pmd_mknotpresent(pmd) (__pmd(pmd_val(pmd) & ~PMD_TYPE_MASK)) +#define pmd_mknotpresent(pmd) (__pmd(pmd_val(pmd) & ~PMD_SECT_VALID)) #define __HAVE_ARCH_PMD_WRITE #define pmd_write(pmd) pte_write(pmd_pte(pmd)) @@ -336,7 +337,6 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, pgprot_t vma_prot); #define pmd_none(pmd) (!pmd_val(pmd)) -#define pmd_present(pmd) (pmd_val(pmd)) #define pmd_bad(pmd) (!(pmd_val(pmd) & PMD_TABLE_BIT))