libvirt guest CPU doesn't match specification: missing features: hle,rtm

error: Failed to start domain mydomain
error: operation failed: guest CPU doesn't match specification: missing features: hle,rtm


1. virsh edit mydomain
2. add the following elements to <cpu></cpu> element.
 

  <feature name="rtm" policy="disable">
  <feature name="hle" policy="disable">

3. virsh start mydomain