runtime-rs: fix the issue of hot-unplug memory smaller

It should do nothing instead of return an error when
hot-unplug the memory to the size smaller than static
plugged memory size.

Signed-off-by: Fupan Li <fupan.lfp@antgroup.com>

src/runtime-rs/crates/hypervisor/src/qemu/inner.rs

@@ -603,15 +603,15 @@ impl QemuInner {
             }
         };
 
-        let coldplugged_mem = megs_to_bytes(self.config.memory_info.default_memory);
+        let coldplugged_mem_mb = self.config.memory_info.default_memory;
+        let coldplugged_mem = megs_to_bytes(coldplugged_mem_mb);
         let new_total_mem = megs_to_bytes(new_total_mem_mb);
 
         if new_total_mem < coldplugged_mem {
-            return Err(anyhow!(
-                "asked to resize to {} M but that is less than cold-plugged memory size ({})",
-                new_total_mem_mb,
-                bytes_to_megs(coldplugged_mem)
-            ));
+            warn!(sl!(), "asked to resize to {} M but that is less than cold-plugged memory size ({}), nothing to do",new_total_mem_mb,
+                bytes_to_megs(coldplugged_mem));
+
+            return Ok((coldplugged_mem_mb, MemoryConfig::default()));
         }
 
         let guest_mem_block_size = qmp.guest_memory_block_size();

src/runtime/virtcontainers/kata_agent.go

@@ -36,6 +36,7 @@ import (
 	"github.com/kata-containers/kata-containers/src/runtime/virtcontainers/pkg/rootless"
 	"github.com/kata-containers/kata-containers/src/runtime/virtcontainers/types"
 	"github.com/kata-containers/kata-containers/src/runtime/virtcontainers/utils"
+	"github.com/kata-containers/kata-containers/src/runtime/virtcontainers/utils/retry"
 
 	ctrAnnotations "github.com/containerd/containerd/pkg/cri/annotations"
 	crioAnnotations "github.com/cri-o/cri-o/pkg/annotations"
@@ -597,7 +598,31 @@ func (k *kataAgent) updateInterface(ctx context.Context, ifc *pbTypes.Interface)
 	ifcReq := &grpc.UpdateInterfaceRequest{
 		Interface: ifc,
 	}
-	resultingInterface, err := k.sendReq(ctx, ifcReq)
+	// Since the network device hotplug is an asynchronous operation,
+	// it's possible that the hotplug operation had returned, but the network device
+	// hasn't ready in guest, thus it's better to retry on this operation to
+	// wait until the device ready in guest.
+
+	var resultingInterface interface{}
+
+	err := retry.Do(func() error {
+		if resInterface, nerr := k.sendReq(ctx, ifcReq); nerr != nil {
+			errMsg := nerr.Error()
+			if !strings.Contains(errMsg, "Link not found") {
+				return retry.Unrecoverable(nerr)
+			}
+
+			return nerr
+		} else {
+			resultingInterface = resInterface
+			return nil
+		}
+	},
+
+		retry.Attempts(20),
+		retry.LastErrorOnly(true),
+		retry.Delay(20*time.Millisecond))
+
 	if err != nil {
 		k.Logger().WithFields(logrus.Fields{
 			"interface-requested": fmt.Sprintf("%+v", ifc),

tests/integration/kubernetes/k8s-cpu-ns.bats

@@ -82,6 +82,9 @@ setup() {
 		[ "$total_cpus_container" -eq "$total_cpus" ] && break
 		sleep 1
 	done
+
+	info "total_cpus_container = $total_cpus_container"
+
 	[ "$total_cpus_container" -eq "$total_cpus" ]
 
 	# Check the total of requests
@@ -117,10 +120,8 @@ setup() {
 teardown() {
 	[ "${KATA_HYPERVISOR}" == "firecracker" ] && skip "test not working see: ${fc_limitations}"
 	[ "${KATA_HYPERVISOR}" == "fc" ] && skip "test not working see: ${fc_limitations}"
-	[ "${KATA_HYPERVISOR}" == "dragonball" ] && skip "test not working see: ${dragonball_limitations}"
-	[ "${KATA_HYPERVISOR}" == "qemu-runtime-rs" ] && skip "Requires CPU hotplug which isn't supported on ${KATA_HYPERVISOR} yet"
 	[ "${KATA_HYPERVISOR}" == "qemu-se-runtime-rs" ] && skip "Requires CPU hotplug which isn't supported on ${KATA_HYPERVISOR} yet"
-	[ "${KATA_HYPERVISOR}" == "cloud-hypervisor" ] && skip "https://github.com/kata-containers/kata-containers/issues/9039"
+	[ "${KATA_HYPERVISOR}" == "qemu-coco-dev*" ] && skip "test not working see: ${fc_limitations}"
 	( [ "${KATA_HYPERVISOR}" == "qemu-tdx" ] || [ "${KATA_HYPERVISOR}" == "qemu-snp" ] || \
 		[ "${KATA_HYPERVISOR}" == "qemu-se" ] ) \
 		&& skip "TEEs do not support memory / CPU hotplug"