diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2018-02-14 14:16:48 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-02-14 13:11:13 +0100 |
| commit | b83ce5ee91471d19c403ff91227204fb37c95fb2 (patch) | |
| tree | 530830b459b756cf431c27cc2000b43b58cdd558 | |
| parent | 116fef6408599dd6ff6996235c50aa692e9b5631 (diff) | |
| download | linux-b83ce5ee91471d19c403ff91227204fb37c95fb2.tar.bz2 | |
x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52
__PHYSICAL_MASK_SHIFT is used to define the mask that helps to extract
physical address from a page table entry.
Although real physical address space available may differ between
machines, it's safe to use 52 as __PHYSICAL_MASK_SHIFT. Unused bits
above log2(MAXPHYADDR) up to bit 51 are reserved and must be 0.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214111656.88514-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/include/asm/page_64_types.h | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h index e1407312c412..f68e6526891d 100644 --- a/arch/x86/include/asm/page_64_types.h +++ b/arch/x86/include/asm/page_64_types.h @@ -52,11 +52,12 @@ #define __START_KERNEL_map _AC(0xffffffff80000000, UL) /* See Documentation/x86/x86_64/mm.txt for a description of the memory map. */ -#ifdef CONFIG_X86_5LEVEL + #define __PHYSICAL_MASK_SHIFT 52 + +#ifdef CONFIG_X86_5LEVEL #define __VIRTUAL_MASK_SHIFT 56 #else -#define __PHYSICAL_MASK_SHIFT 46 #define __VIRTUAL_MASK_SHIFT 47 #endif |