diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 58fd40a3bf52..ed26e14cfc2f 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -850,9 +850,9 @@ 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.