$NetBSD: patch-SA45835,v 1.1 2011/09/10 18:35:51 bouyer Exp $

--- xen/include/asm-x86/x86_64/uaccess.h.orig	2008-04-25 15:03:12.000000000 +0200
+++ xen/include/asm-x86/x86_64/uaccess.h	2011-09-10 20:26:42.000000000 +0200
@@ -8,7 +8,7 @@
  * non-canonical address (and thus fault) before ever reaching VIRT_START.
  */
 #define __addr_ok(addr) \
-    (((unsigned long)(addr) < (1UL<<48)) || \
+    (((unsigned long)(addr) < (1UL<<47)) || \
      ((unsigned long)(addr) >= HYPERVISOR_VIRT_END))
 
 #define access_ok(addr, size) (__addr_ok(addr))