- Faster mount detection for linux kernel 5.10+ using openat2 speeding up pod churn rates. On Kernel versions less 5.10, it will fallback to using the original way of detecting mount points i.e by parsing /proc/mounts. ([#109217](https://github.com/kubernetes/kubernetes/pull/109217), [@manugupt1](https://github.com/manugupt1))

- Kubeadm: upgrade supports fallback to the nearest known etcd version if an unknown k8s version is passed ([#88373](https://github.com/kubernetes/kubernetes/pull/88373), [@SataQiu](https://github.com/SataQiu)) [SIG Cluster Lifecycle]

* Fixed binding of block PersistentVolumes / PersistentVolumeClaims when BlockVolume feature is off. ([#84049](https://github.com/kubernetes/kubernetes/pull/84049), [@jsafrane](https://github.com/jsafrane))
* kube-scheduler now fallbacks to emitting events using core/v1 Events when events.k8s.io/v1beta1 is disabled. ([#83692](https://github.com/kubernetes/kubernetes/pull/83692), [@yastij](https://github.com/yastij))

* Restored the ability of kubectl running inside a pod to consume resource files specifying a different namespace than the one the pod is...

  - `kube-apiserver` now only aggregates openapi schemas from `/openapi/v2` endpoints of aggregated API servers. The fallback to aggregate from `/swagger.json` has been removed. Ensure aggregated API servers provide schema information via `/openapi/v2` (available since v1.10). ([#73441](https://github.com/kubernetes/kubernetes/pull/73441), [@roycaihw](https://github.com/roycaihw))...

#### DaemonSet
* [beta] DaemonSet supports history and rollback. See [Performing a Rollback on a DaemonSet](https://kubernetes.io/docs/tasks/manage-daemon/rollback-daemon-set/).

#### Deployments

- proxy/transport now supports Content-Encoding: deflate ([#76551](https://github.com/kubernetes/kubernetes/pull/76551), [@JieJhih](https://github.com/JieJhih))
- Admission webhooks are now properly called for `scale` and `deployments/rollback` subresources. ([#76849](https://github.com/kubernetes/kubernetes/pull/76849), [@liggitt](https://github.com/liggitt))

## API Changes

  * Minimum memory limit is 4MB. This is a docker limitation
  * Minimum CPU limits is 10m. This is a Linux Kernel limitation
  * “kubectl rollout undo” (i.e. rollback) will hang on paused deployments, because
paused deployments can’t be rolled back (this is expected), and the command
waits for rollback events to return the result. Users should use “kubectl
rollout resume” to resume a deployment before rolling back.

- Added `kubectl node drain` helper callbacks `OnPodDeletionOrEvictionStarted`
  and `OnPodDeletionOrEvictionFailed`; people extending `kubectl` can use these
  new callbacks for more granularity. Deprecated the `OnPodDeletedOrEvicted`
  node drain helper callback. ([#117502](https://github.com/kubernetes/kubernetes/pull/117502), [@adilGhaffarDev](https://github.com/adilGhaffarDev))

* Remove the restart-kube-proxy and restart-apiserver functions ([#23180](https://github.com/kubernetes/kubernetes/pull/23180), [@roberthbailey](https://github.com/roberthbailey))
* Copy annotations back from RS to Deployment on rollback ([#23160](https://github.com/kubernetes/kubernetes/pull/23160), [@janetkuo](https://github.com/janetkuo))