diff -r 9ddf07022b3f xen/common/sched_credit.c
--- a/xen/common/sched_credit.c	Wed Feb 09 10:29:53 2011 +0000
+++ b/xen/common/sched_credit.c	Wed Feb 09 10:51:05 2011 +0000
@@ -381,6 +381,14 @@
         per_cpu(schedule_data, cpu).sched_priv = spc;
 
     /* Start off idling... */
+    if ( !is_idle_vcpu(per_cpu(schedule_data, cpu).curr) )
+    {
+        printk("%s: curr d%dv%d on p%d!\n",
+               __func__,
+               per_cpu(schedule_data, cpu).curr->domain->domain_id,
+               per_cpu(schedule_data, cpu).curr->vcpu_id,
+               cpu);
+    }
     BUG_ON(!is_idle_vcpu(per_cpu(schedule_data, cpu).curr));
     cpu_set(cpu, prv->idlers);