[PATCH] x86_64: Add a guard page at the end of the 47bit address space
This works around a bug in the AMD K8 CPUs.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-x86_64/processor.h b/include/asm-x86_64/processor.h
index f0581c3..9f74a28 100644
--- a/include/asm-x86_64/processor.h
+++ b/include/asm-x86_64/processor.h
@@ -159,9 +159,9 @@
/*
- * User space process size. 47bits.
+ * User space process size. 47bits minus one guard page.
*/
-#define TASK_SIZE (0x800000000000UL)
+#define TASK_SIZE (0x800000000000UL - 4096)
/* This decides where the kernel will search for a free chunk of vm
* space during mmap's.