[Xen-changelog] [xen-unstable] Intel EPT: Fix out of range right shift on 32-bit host

[Xen patchbot-unstable <patchbot-unstable@xxxxxxxxxxxxxxxxxxx>]

# HG changeset patch
# User Keir Fraser <keir.fraser@xxxxxxxxxx>
# Date 1281368418 -3600
# Node ID 9e58c46ee63b3201a0a08b631ed4b79c72cf91a3
# Parent  07ea977397e0f7bde649d2542bba037fd2a951bf
Intel EPT: Fix out of range right shift on 32-bit host

Currently, there has a logic to check whether the EPT GFN is exceeding
guest physical address width. It uses right shift(>>) to implement the
check. But the right shift count is greater than the width of the
type(unsigned long = 32) under the PAE. And this will cause guest boot
fail under PAE with EPT supported.

Signed-off-by: Li Xin <xin.li@xxxxxxxxx>
Signed-off-by: Zhang Yang <yang.z.zhang@xxxxxxxxx>
---
 xen/arch/x86/mm/hap/p2m-ept.c |    2 +-
 1 files changed, 1 insertion(+), 1 deletion(-)

diff -r 07ea977397e0 -r 9e58c46ee63b xen/arch/x86/mm/hap/p2m-ept.c
--- a/xen/arch/x86/mm/hap/p2m-ept.c     Mon Aug 09 16:39:09 2010 +0100
+++ b/xen/arch/x86/mm/hap/p2m-ept.c     Mon Aug 09 16:40:18 2010 +0100
@@ -267,7 +267,7 @@ ept_set_entry(struct domain *d, unsigned
      * 3. passing a valid order.
      */
     if ( ((gfn | mfn_x(mfn)) & ((1UL << order) - 1)) ||
-         (gfn >> ((ept_get_wl(d) + 1) * EPT_TABLE_ORDER)) ||
+         ((u64)gfn >> ((ept_get_wl(d) + 1) * EPT_TABLE_ORDER)) ||
          (order % EPT_TABLE_ORDER) )
         return 0;
 

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog