[Xen-devel] xen: relax restrictions on reserved bits in L3 for 32on64 x86 guests

[Ian Campbell <Ian.Campbell@xxxxxxxxxx>]

xen: relax restrictions on reserved bits in L3 for 32on64 x86 guests

A 32on64 guest cannot copy an existing pinned L3 entry to use as a new
L3 because COMPAT_L3_DISALLOW_MASK contains bits which are added to L3
entries by adjust_guest_l3e (U/S & R/W) or by the hardware (A & D).

Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>

diff -r bb1a67a7db26 xen/include/asm-x86/x86_64/page.h
--- a/xen/include/asm-x86/x86_64/page.h Thu Oct 16 15:46:04 2008 +0100
+++ b/xen/include/asm-x86/x86_64/page.h Fri Oct 24 11:05:43 2008 +0100
@@ -119,7 +119,7 @@ typedef l4_pgentry_t root_pgentry_t;
 #define L3_DISALLOW_MASK (BASE_DISALLOW_MASK)
 #define L4_DISALLOW_MASK (BASE_DISALLOW_MASK)
 
-#define COMPAT_L3_DISALLOW_MASK 0xFFFFF1FEU
+#define COMPAT_L3_DISALLOW_MASK 0xFFFFF198U
 
 #define PAGE_HYPERVISOR         (__PAGE_HYPERVISOR         | _PAGE_GLOBAL)
 #define PAGE_HYPERVISOR_NOCACHE (__PAGE_HYPERVISOR_NOCACHE | _PAGE_GLOBAL)



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