I am trying to run nested hypervisors to do some openstack experiments. I seem to be able to run xen-on-xen with no problems but if i try to run kvm-on-xen the system seems to spontaneously reboot. I get the same results with xen 4.3 or 4.4. The dom0 is running fedora-20 The experiment environment is Centos6 with RDO Any hints on what the problem may be or a good place to start to look to diagnose it? -- Alvin Starr.