Kubelet flag `--enforce-node-allocatable` with a default value of `pods` is added which will make kubelet create a top level cgroup for all pods to enforce Node Allocatable. Optionally, `system-reserved` & `kube-reserved` values can also be specified separated by comma to enforce node allocatable on cgroups specified via `--system-reserved-cgroup` & `--kube-reserved-cgroup` respectively. Note the default value of the latter flags are "". ([#41234](https://github.com/kubernetes/kubernetes/pull/41234),...

 - Kubeadm: remove the automatic detection and matching of cgroup drivers for Docker. For new clusters if you have not configured the cgroup driver explicitly you might get a failure in the `kubelet` on driver mismatch (kubeadm clusters should be using the `systemd` driver). Also remove the `IsDockerSystemdCheck` preflight check (warning) that checks if the Docker cgroup driver is set to `systemd`. Ideally such detection / coordination should be on the side of CRI...

  vendor: Updated `k8s.io/system-validators` to `v1.12.1`. The cgroups validator now throws an error instead of a warning if cgroups v1 is detected on the host and the provided KubeletVersion is `v1.35` or newer.
  

* kubeadm now detects the Docker cgroup driver and starts the kubelet with the matching driver. This eliminates a common error experienced by new users in when the Docker cgroup driver is not the same as the one set for the kubelet due to different Linux distributions setting different cgroup drivers for Docker, making it hard to start the kubelet properly.

* Set fsGroup by securityContext.fsGroup in azure file. However,f user both sets gid=xxx in mountOptions in azure storage class and securityContext.fsGroup, gid=xxx setting in mountOptions takes precedence. ([#58316](https://github.com/kubernetes/kubernetes/pull/58316), [@andyzhangx](https://github.com/andyzhangx))

### SIG Node

- Fixed a bug in previous releases where a pod could be placed inside another pod's cgroup when specifying --cgroup-root ([#70678](https://github.com/kubernetes/kubernetes/pull/70678), [@dashpole](https://github.com/dashpole))

* Default resourceGroup should be used when the value of annotation azure-load-balancer-resource-group is an empty string. ([#79514](https://github.com/kubernetes/kubernetes/pull/79514), [@feiskyer](https://github.com/feiskyer))
* Remove pids cgroup controller requirement when related feature gates are disabled ([#79073](https://github.com/kubernetes/kubernetes/pull/79073), [@rafatio](https://github.com/rafatio))

- Fixed a bug where the kubelet ephemerally failed with `failed to initialize top level QOS containers: root container [kubepods] doesn't exist`, due to the cpuset cgroup being deleted on cgroup v2 with systemd cgroup manager.
   ([#125923](https://github.com/kubernetes/kubernetes/pull/125923), [@haircommander](https://github.com/haircommander)) [SIG Node and Testing]

  are now in the apps/v1beta2 group and version.

- The apps/v1beta2 group version adds a Scale subresource for the StatefulSet
kind.

- All kinds in the apps/v1beta2 group version add a corresponding conditions
  kind.

#### Behavioral Changes

 - For all kinds in the API group version, a spec.selector default value is no longer

- Fixed occasional pod cgroup freeze when using cgroup v1 and systemd driver.