- Do not detach volume if mount in progress ([#71145](https://github.com/kubernetes/kubernetes/pull/71145), [@gnufied](https://github.com/gnufied))
- The runtimeHandler field on the RuntimeClass resource now accepts the empty string. ([#69550](https://github.com/kubernetes/kubernetes/pull/69550), [@tallclair](https://github.com/tallclair))

          "uid": "uidValue",
          "resourceVersion": "resourceVersionValue",
          "kubeletConfigKey": "kubeletConfigKeyValue"
        }
      },
      "error": "errorValue"
    },
    "runtimeHandlers": [
      {
        "name": "nameValue",
        "features": {
          "recursiveReadOnlyMounts": true
        }
      }
    ]
  }

          "uid": "uidValue",
          "resourceVersion": "resourceVersionValue",
          "kubeletConfigKey": "kubeletConfigKeyValue"
        }
      },
      "error": "errorValue"
    },
    "runtimeHandlers": [
      {
        "name": "nameValue",
        "features": {
          "recursiveReadOnlyMounts": true
        }
      }
    ]
  }

    kubeletVersion: kubeletVersionValue
    machineID: machineIDValue
    operatingSystem: operatingSystemValue
    osImage: osImageValue
    systemUUID: systemUUIDValue
  phase: phaseValue
  runtimeHandlers:
  - features:
      recursiveReadOnlyMounts: true
    name: nameValue
  volumesAttached:
  - devicePath: devicePathValue
    name: nameValue
  volumesInUse:

    kubeletVersion: kubeletVersionValue
    machineID: machineIDValue
    operatingSystem: operatingSystemValue
    osImage: osImageValue
    systemUUID: systemUUIDValue
  phase: phaseValue
  runtimeHandlers:
  - features:
      recursiveReadOnlyMounts: true
    name: nameValue
  volumesAttached:
  - devicePath: devicePathValue
    name: nameValue
  volumesInUse:

    * Introduce a RuntimeClass v1beta1 API. This new beta API renames `runtimeHandler` to `handler`, makes it a required field, and cuts out the spec (handler is a top-level field).

	// for update
	if !nodeConfigSourceInUse(oldNode) && oldNode != nil {
		node.Spec.ConfigSource = nil
	}

	if !utilfeature.DefaultFeatureGate.Enabled(features.RecursiveReadOnlyMounts) {
		node.Status.RuntimeHandlers = nil
	}
}

// nodeConfigSourceInUse returns true if node's Spec ConfigSource is set(used)
func nodeConfigSourceInUse(node *api.Node) bool {
	if node == nil {
		return false
	}

* kubeadm: fix a possible scenario where kubeadm can pull much newer control-plane images ([#69301](https://github.com/kubernetes/kubernetes/pull/69301), [@neolit123](https://github.com/neolit123))
* The runtimeHandler field on the RuntimeClass resource now accepts the empty string. ([#69550](https://github.com/kubernetes/kubernetes/pull/69550), [@tallclair](https://github.com/tallclair))

		nodestatus.DaemonEndpoints(kl.daemonEndpoints),
		nodestatus.Images(kl.nodeStatusMaxImages, kl.imageManager.GetImageList),
		nodestatus.GoRuntime(),
		nodestatus.RuntimeHandlers(kl.runtimeState.runtimeHandlers),
	)

	setters = append(setters,
		nodestatus.MemoryPressureCondition(kl.clock.Now, kl.evictionManager.IsUnderMemoryPressure, kl.recordNodeStatusEvent),

			// Use DefBuckets for now, will customize the buckets if necessary.
			Buckets:        metrics.DefBuckets,
			StabilityLevel: metrics.ALPHA,
		},
		[]string{"runtime_handler"},
	)
	// RunPodSandboxErrors is a Counter that tracks the cumulative number of Pod Sandbox operations errors.
	// Broken down by RuntimeClass.Handler.
	RunPodSandboxErrors = metrics.NewCounterVec(