[PATCH 5/5] x86/mm: Allow userspace have mapping above 47-bit

From: Kirill A. Shutemov
Date: Thu Jun 22 2017 - 08:27:16 EST


All bits and pieces now in place and we can allow userspace to have VMAs
above 47-bit.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/processor.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 42b87689ecd7..0ed01fdd7fa2 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -844,9 +844,9 @@ static inline void spin_lock_prefetch(const void *x)
* particular problem by preventing anything from being mapped
* at the maximum canonical address.
*/
-#define TASK_SIZE_MAX ((1UL << 47) - PAGE_SIZE)
+#define TASK_SIZE_MAX ((1UL << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE)

-#define DEFAULT_MAP_WINDOW TASK_SIZE_MAX
+#define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE)

/* This decides where the kernel will search for a free chunk of vm
* space during mmap's.
--
2.11.0