CSI support for Windows nodes moves to GA in the 1.22 release. In Kubernetes v1.22, Windows privileged containers are only an alpha feature. To allow using CSI storage on Windows nodes, [CSIProxy](https://github.com/kubernetes-csi/csi-proxy) enables CSI node plugins to be deployed as unprivileged pods, using the proxy to perform privileged storage operations on the node.

- The alpha feature `AnyVolumeDataSource` enables PersistentVolumeClaim objects to use the spec.dataSource field to reference a custom type as a data source ([#88636](https://github.com/kubernetes/kubernetes/pull/88636), [@bswartz](https://github.com/bswartz)) [SIG Apps and Storage]

### API Change

- 'ACTION REQUIRED: The Dynamic Resource Allocation (DRA) driver's DaemonSet
  must be deployed with a service account that enables writing ResourceSlice
  and reading ResourceClaim objects.'
   ([#125163](https://github.com/kubernetes/kubernetes/pull/125163), [@pohly](https://github.com/pohly)) [SIG Auth, Node and Testing]

* The Kubelet's deprecated `--allow-privileged` flag now defaults to true. This enables users to stop setting `--allow-privileged` in order to transition to `PodSecurityPolicy`. Previously, users had to continue setting `--allow-privileged`, because the default was false. ([#63442](https://github.com/kubernetes/kubernetes/pull/63442),...

* Add support for PodSecurityPolicy on GCE: `ENABLE_POD_SECURITY_POLICY=true` enables the admission controller, and installs policies for default addons. ([#52367](https://github.com/kubernetes/kubernetes/pull/52367), [@tallclair](https://github.com/tallclair))

* [alpha] Adding admissionregistration API group which enables dynamic registration of initializers and external admission webhooks. ([#46294](https://github.com/kubernetes/kubernetes/pull/46294), [@caesarxuchao](https://github.com/caesarxuchao))


### **Application Deployment**

### Beta
- The Kubernetes Volume Snapshot feature has been moved to beta. The VolumeSnapshotDataSource feature gate is on by default in this release. This feature enables you to take a snapshot of a volume (if supported by the CSI driver), and use the snapshot to provision a new volume, pre-populated with data from the snapshot.

*   Block Storage (Cinder) V3 is now supported.
*   Load Balancer (Octavia) V2 is now supported, in addition to Neutron LBaaS V2.
*   Neutron LBaas V1 support has been removed.

This work enables Kubernetes to take full advantage of the relevant services as exposed by OpenStack clouds. Refer to the [Cloud Providers](https://kubernetes.io/docs/concepts/cluster-administration/cloud-providers/#openstack) documentation for more information.

Pod Priority and Preemption in Kubernetes ([#564](https://github.com/kubernetes/enhancements/issues/564))

- Pod priority and preemption enables Kubernetes scheduler to schedule more important Pods first and when cluster is out of resources, it removes less important pods to create room for more important ones. The importance is specified by priority.

These extension points can now be abstracted away due to their irrelevance for most users.

### CSI Migration updates

CSI Migration enables the replacement of existing in-tree storage plugins such as `kubernetes.io/gce-pd` or `kubernetes.io/aws-ebs` with a corresponding CSI driver.
If CSI Migration is working properly, Kubernetes end users shouldn’t notice a difference.