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| author | Will Deacon <will.deacon@arm.com> | 2016-06-07 17:57:54 +0100 |
|---|---|---|
| committer | Jiri Slaby <jslaby@suse.cz> | 2016-07-21 08:36:02 +0200 |
| commit | 87119310890eee0731bd5a5ad7c056c3ccd83c01 (patch) | |
| tree | 081e6effb0c3bc3da32bfb68e6442c7591918cc3 | |
| parent | 75815edd37f0623d732065f710bcf475364dc07b (diff) | |
| download | lwn-87119310890eee0731bd5a5ad7c056c3ccd83c01.tar.gz lwn-87119310890eee0731bd5a5ad7c056c3ccd83c01.zip | |
ARM: 8578/1: mm: ensure pmd_present only checks the valid bit
commit 624531886987f0f1b5d01fb598034d039198e090 upstream.
In a subsequent patch, pmd_mknotpresent will clear the valid bit of the
pmd entry, resulting in a not-present entry from the hardware's
perspective. Unfortunately, pmd_present simply checks for a non-zero pmd
value and will therefore continue to return true even after a
pmd_mknotpresent operation. Since pmd_mknotpresent is only used for
managing huge entries, this is only an issue for the 3-level case.
This patch fixes the 3-level pmd_present implementation to take into
account the valid bit. For bisectability, the change is made before the
fix to pmd_mknotpresent.
[catalin.marinas@arm.com: comment update regarding pmd_mknotpresent patch]
Fixes: 8d9625070073 ("ARM: mm: Transparent huge page support for LPAE systems.")
Cc: Russell King <linux@armlinux.org.uk>
Cc: Steve Capper <Steve.Capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
| -rw-r--r-- | arch/arm/include/asm/pgtable-2level.h | 1 | ||||
| -rw-r--r-- | arch/arm/include/asm/pgtable-3level.h | 1 | ||||
| -rw-r--r-- | arch/arm/include/asm/pgtable.h | 1 |
3 files changed, 2 insertions, 1 deletions
diff --git a/arch/arm/include/asm/pgtable-2level.h b/arch/arm/include/asm/pgtable-2level.h index c98c9c89b95c..3f1b3a4150b6 100644 --- a/arch/arm/include/asm/pgtable-2level.h +++ b/arch/arm/include/asm/pgtable-2level.h @@ -162,6 +162,7 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr) } #define pmd_bad(pmd) (pmd_val(pmd) & 2) +#define pmd_present(pmd) (pmd_val(pmd)) #define copy_pmd(pmdpd,pmdps) \ do { \ diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h index 6a171d0afc12..8afa39f81477 100644 --- a/arch/arm/include/asm/pgtable-3level.h +++ b/arch/arm/include/asm/pgtable-3level.h @@ -209,6 +209,7 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr) : !!(pmd_val(pmd) & (val))) #define pmd_isclear(pmd, val) (!(pmd_val(pmd) & (val))) +#define pmd_present(pmd) (pmd_isset((pmd), L_PMD_SECT_VALID)) #define pmd_young(pmd) (pmd_isset((pmd), PMD_SECT_AF)) #define __HAVE_ARCH_PMD_WRITE diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index a348bfd34f66..5bdf9864fb00 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -182,7 +182,6 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) #define pmd_none(pmd) (!pmd_val(pmd)) -#define pmd_present(pmd) (pmd_val(pmd)) static inline pte_t *pmd_page_vaddr(pmd_t pmd) { |