# HG changeset 15173 patch
# User Ian Campbell <ian.campbell@xensource.com>
# Node ID 88e41a91301c109b99443db3a4bf3c8e6bbad042
# Parent  f2d2d5f18543de04191c1f5e22471e74d8767147
Correct 32on64 handling of VCPUOP_register_runstate_memory_area.  We
were copying too many bytes from the guest so the test for
area.addr.h.c != area.addr.p was failing.

Added a WARN_ON to the kernel to catch this case. It would be a BUG_ON
but this would break the new kernel on older hypervisors and the only
real problem is that stolen time is not updated, which we can live
with.

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

Index: 2007-05-14/xen/arch/x86/x86_64/domain.c
===================================================================
--- 2007-05-14.orig/xen/arch/x86/x86_64/domain.c	2007-04-23 10:01:42.000000000 +0200
+++ 2007-05-14/xen/arch/x86/x86_64/domain.c	2007-07-02 10:47:40.000000000 +0200
@@ -22,8 +22,10 @@ arch_compat_vcpu_op(
         struct compat_vcpu_register_runstate_memory_area area;
         struct compat_vcpu_runstate_info info;
 
+        area.addr.p = 0;
+
         rc = -EFAULT;
-        if ( copy_from_guest(&area, arg, 1) )
+        if ( copy_from_guest(&area.addr.h, arg, 1) )
             break;
 
         if ( area.addr.h.c != area.addr.p ||