(or even be just another bound type parameter).
In a process of repeated simplification, the bound type parameters in each type
argument are substituted with the respective type arguments for those type
parameters until each type argument is free of bound type parameters.
</p>

<p>
If type arguments contain cyclic references to themselves
through bound type parameters, simplification and thus type
inference fails.

* PVC may not be synced to controller local cache in time if PV is bound by external PV binder (e.g. kube-scheduler), double check if PVC is not found to prevent reclaiming PV wrongly. ([#67062](https://github.com/kubernetes/kubernetes/pull/67062), [@cofyc](https://github.com/cofyc))

- Volume binding: report UnschedulableAndUnresolvable status instead of an error when bound PVs not found ([#95541](https://github.com/kubernetes/kubernetes/pull/95541), [@cofyc](https://github.com/cofyc)) [SIG Apps, Scheduling and Storage]

volumes created using vSphere. ([#59328](https://github.com/kubernetes/kubernetes/pull/59328), [@divyenpatel](https://github.com/divyenpatel))

* Emit number of bound and unbound persistent volumes as Metrics. This PR adds four kinds of Volume Metrics for kube-controller-manager: bound PVC numbers, unbound PVC numbers, bound PV numbers and unbound PV numbers. The PVC metrics use namespace as dimension and the PV metrics use StorageClassName as its dimension. With these metrics we can better...

  // are also valid here.
  optional PersistentVolumeClaimSpec spec = 2;
}

// PersistentVolumeClaimVolumeSource references the user's PVC in the same namespace.
// This volume finds the bound PV and mounts that volume for the pod. A
// PersistentVolumeClaimVolumeSource is, essentially, a wrapper around another
// type of volume that is owned by someone else (the system).
message PersistentVolumeClaimVolumeSource {

- Allowed creating ServiceAccount tokens bound to Node objects.
  This allows users to bind a service account token's validity to a named Node object, similar to Pod bound tokens.

 - `kubeadm`: a separate "super-admin.conf" file is now deployed. The User in `admin.conf` is now bound to a new RBAC Group `kubeadm:cluster-admins` that has `cluster-admin` `ClusterRole` access. The User in `super-admin.conf` is now bound to the `system:masters` built-in super-powers / break-glass Group that can bypass RBAC. Before this change, the default `admin.conf` was bound to `system:masters` Group, which was undesired. Executing `kubeadm init phase kubeconfig all` or just `kubeadm...

- Fixed consolidate logs for `instance not found` error
  Fixed skip `not found` nodes when reconciling LB backend address pools ([#105188](https://github.com/kubernetes/kubernetes/pull/105188), [@nilo19](https://github.com/nilo19))

Another feature moving to GA in v1.22 is CSI Service Account Token support. This feature allows CSI drivers to use pods' [bound service account tokens](https://kubernetes.io/docs/reference/access-authn-authz/service-accounts-admin/#bound-service-account-token-volume) instead of a more privileged identity. It also provides control over to re-publishing these volumes, so that short-lived tokens can be refreshed.

  * Advanced scheduling can be performed with [taints and tolerations](https://kubernetes.io/docs/concepts/configuration/assign-pod-node/#taints-and-tolerations-beta-feature)
* You can now specify (per pod) how long a pod should stay bound to a node, when there is a node problem.
* Various storage features have graduated to GA:
  * StorageClass pre-installed and set as default on Azure, AWS, GCE, OpenStack, and vSphere