fix changging the stopped vm's subnets, the vm cann't start normally (#2463)

Co-authored-by: yuanliu <yuanliu@cmss.chinamobile.com>

Author: 2 people

pkg/controller/pod.go

@@ -547,6 +547,39 @@ func (c *Controller) getPodKubeovnNets(pod *v1.Pod) ([]*kubeovnNet, error) {
 	return podNets, nil
 }
 
+func (c *Controller) changeVMSubnet(vmName, namespace, providerName, subnetName string, pod *v1.Pod) error {
+	ipName := ovs.PodNameToPortName(vmName, namespace, providerName)
+	ipCr, err := c.config.KubeOvnClient.KubeovnV1().IPs().Get(context.Background(), ipName, metav1.GetOptions{})
+	if err != nil {
+		if !k8serrors.IsNotFound(err) {
+			errMsg := fmt.Errorf("failed to get ip CR %s: %v", ipName, err)
+			klog.Error(errMsg)
+			return errMsg
+		}
+		// the returned pointer is not nil if the CR does not exist
+		ipCr = nil
+	}
+	if ipCr != nil {
+		if ipCr.Spec.Subnet != subnetName {
+			key := fmt.Sprintf("%s/%s", pod.Namespace, vmName)
+			ports, err := c.ovnClient.ListPodLogicalSwitchPorts(key)
+			if err != nil {
+				klog.Errorf("failed to list lsps of pod '%s', %v", pod.Name, err)
+				return err
+			}
+			for _, port := range ports {
+				// when lsp is deleted, the port of pod is deleted from any port-group automatically.
+				klog.Infof("gc logical switch port %s", port.Name)
+				if err := c.ovnLegacyClient.DeleteLogicalSwitchPort(port.Name); err != nil {
+					klog.Errorf("failed to delete lsp %s, %v", port.Name, err)
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
 func (c *Controller) handleAddPod(key string) error {
 	namespace, name, err := cache.SplitMetaNamespaceKey(key)
 	if err != nil {
@@ -603,6 +636,10 @@ func (c *Controller) handleAddPod(key string) error {
 		}
 		if isVmPod && c.config.EnableKeepVmIP {
 			pod.Annotations[fmt.Sprintf(util.VmTemplate, podNet.ProviderName)] = vmName
+			if err := c.changeVMSubnet(vmName, namespace, podNet.ProviderName, subnet.Name, pod); err != nil {
+				klog.Errorf("change subnet of pod %s/%s to %s failed: %v", namespace, name, subnet.Name, err)
+				return err
+			}
 		}
 
 		if err := util.ValidatePodCidr(podNet.Subnet.Spec.CIDRBlock, ipStr); err != nil {