- Kubernetes v1.13 moves support for Container Storage Interface to GA. As part of this move Kubernetes now supports CSI v1.0.0 and deprecates support for CSI 0.3 and older releases. Older CSI drivers must be updated to CSI 1.0 and moved to the new kubelet plugin registration directory in order to work with Kubernetes 1.15+. ([#71020](https://github.com/kubernetes/kubernetes/pull/71020), [@saad-ali](https://github.com/saad-ali))

resources should change to reference the `policy` API group after upgrading to 1.11. ([#54933](https://github.com/kubernetes/kubernetes/pull/54933), [@php-coder](https://github.com/php-coder))

* Add `--enable-admission-plugins` `--disable-admission-plugins` flags and deprecate `--admission-control`. When using the separate flag, the order in which they're specified doesn't matter.  ([#58123](https://github.com/kubernetes/kubernetes/pull/58123), [@hzxuzhonghu](https://github.com/hzxuzhonghu))...

* kubelet: fix bug where `runAsUser: MustRunAsNonRoot` strategy didn't reject a pod with a non-numeric `USER`. ([#56711](https://github.com/kubernetes/kubernetes/pull/56711), [@php-coder](https://github.com/php-coder))
* Fix a bug in GCE multizonal clusters where PersistentVolumes were sometimes created in zones without nodes. ([#52322](https://github.com/kubernetes/kubernetes/pull/52322), [@davidz627](https://github.com/davidz627))

    * Fixes volume detach from shutdown nodes.
* Enable insertId generation, and update Stackdriver Logging Agent image to 0.5-1.5.36-1-k8s. This help reduce log duplication and guarantee log order. ([#68920](https://github.com/kubernetes/kubernetes/pull/68920), [@qingling128](https://github.com/qingling128))

* kubelet: fix bug where `runAsUser: MustRunAsNonRoot` strategy didn't reject a pod with a non-numeric `USER`. ([#56503](https://github.com/kubernetes/kubernetes/pull/56503), [@php-coder](https://github.com/php-coder))
* kube-proxy addon tolerates all NoExecute and NoSchedule taints by default. ([#56589](https://github.com/kubernetes/kubernetes/pull/56589), [@mindprince](https://github.com/mindprince))

Please see the [Releases Page](https://github.com/kubernetes/kubernetes/releases) for older releases.

Release notes of older releases can be found in:
- [CHANGELOG-1.2.md](https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG/CHANGELOG-1.2.md)

* kubelet: Fix bug where `runAsUser: MustRunAsNonRoot` strategy didn't reject a pod with a non-numeric `USER`. ([#56708](https://github.com/kubernetes/kubernetes/pull/56708), [@php-coder](https://github.com/php-coder))
* Add iptables rules to allow Pod traffic even when default iptables policy is to reject. ([#52569](https://github.com/kubernetes/kubernetes/pull/52569), [@tmjd](https://github.com/tmjd))

however, kubectl v1.21 and older do not support the new API for ephemeral containers.

## Changelog since v1.17.6

## Changes by Kind

### API Change

- Resolve regression in metadata.managedFields handling in update/patch requests submitted by older API clients ([#92008](https://github.com/kubernetes/kubernetes/pull/92008), [@apelisse](https://github.com/apelisse)) [SIG API Machinery and Testing]

### Feature

- `kubeadm`: will now allow deploying a kubelet that is 3 versions older than the version of `kubeadm` (N-3). This aligns with the recent change made by SIG Architecture that extends the support skew between the control plane and kubelets. Tolerate this new kubelet skew for the commands `init`, `join` and `upgrade`. Note that if the `kubeadm` user applies a control plane version that is older than the `kubeadm` version (N-1 maximum) then the skew between the kubelet and control...