code: func (rs *Registrations) Validate(internalcfg *kubeadmapi.ClusterConfiguration) field.ErrorList {
  	allErrs := field.ErrorList{}
  	for kind, registration := range *rs {
  		allErrs = append(allErrs, registration.ValidateFunc(internalcfg, field.NewPath(string(kind)))...)
  	}
  	return allErrs
  }
docs: // Validate validates the ComponentConfig parts of the internal kubeadm API type