Check feature flag supervisor_mode_kernel in dom0 builder.

Signed-off-by: Keir Fraser <keir@xensource.com>

diff --git a/xen/arch/x86/domain_build.c b/xen/arch/x86/domain_build.c
index 361ca2485e7ff5a3900447ad3b32652539e92521..f60ac47fc68be162d2cdacd36bd9d92658b3886d 100644 (file)
--- a/xen/arch/x86/domain_build.c
+++ b/xen/arch/x86/domain_build.c
@@ -802,6 +802,14 @@ int construct_dom0(struct domain *d,
         v->arch.guest_context.user_regs.fs &= ~3;
         v->arch.guest_context.user_regs.gs &= ~3;
         printk("Dom0 runs in ring 0 (supervisor mode)\n");
+        if ( !test_bit(XENFEAT_supervisor_mode_kernel,
+                       dom0_features_supported) )
+            panic("Dom0 does not support supervisor-mode execution\n");
+    }
+    else
+    {
+        if ( test_bit(XENFEAT_supervisor_mode_kernel, dom0_features_required) )
+            panic("Dom0 requires supervisor-mode execution\n");
     }
 
     rc = 0;