code: func (svm *serviceVM) hotAddVHDs(mvds ...hcsshim.MappedVirtualDisk) error {
  	if err := svm.getStartError(); err != nil {
  		return err
  	}
  	return svm.hotAddVHDsAtStart(mvds...)
  }
docs: // hotAddVHDs waits for the service vm to start and then attaches the vhds.