provider can now be specified as environment variables. When we convert the OpenStack cloud provider to run in an external process, we can now use the kubernetes Secrets capability to inject the OS_* variables. This way we can specify the cloud configuration as a configmap, and specify secrets for the userid/password information. The configmap is mounted as a file, and the secrets are made available as environment variables. The external controller itself runs as a pod/daemonset. For backward compatibility,...

* Add MAX_PODS_PER_NODE env so that GCE/GKE user can use it to specify the default max pods per node for the cluster. IP_ALIAS_SIZE will be changed accordingly. Must have ip alias enabled. ([#63451](https://github.com/kubernetes/kubernetes/pull/63451), [@grayluck](https://github.com/grayluck))

### Other (Cleanup or Flake)

- By enabling the alpha `CloudNodeIPs` feature gate in kubelet and the cloud
  provider, you can now specify a dual-stack `--node-ip` value (when using an

* kube-apiserver: the `Priority` admission plugin is now enabled by default when using `--enable-admission-plugins`. If using `--admission-control` to fully specify the set of admission plugins, the `Priority` admission plugin should be added if using the `PodPriority` feature, which is enabled by default in 1.11. ([#65739](https://github.com/kubernetes/kubernetes/pull/65739), [@liggitt](https://github.com/liggitt))...

#### Storage

* [stable] Mount options

  * The ability to specify mount options for volumes is moved from beta to stable.

  * A new `MountOptions` field in the `PersistentVolume` spec is available to specify mount options. This field replaces an annotation.

- Containers which specify a `startupProbe` but not a `readinessProbe` were previously considered "ready" before the `startupProbe` completed, but are now considered "not-ready". ([#92196](https://github.com/kubernetes/kubernetes/pull/92196), [@thockin](https://github.com/thockin))...

* [fluentd-gcp addon] Bump fluentd-gcp-scaler to v0.5.2 to pick up security fixes. ([#76762](https://github.com/kubernetes/kubernetes/pull/76762), [@serathius](https://github.com/serathius))
* specify azure file share name in azure file plugin ([#76988](https://github.com/kubernetes/kubernetes/pull/76988), [@andyzhangx](https://github.com/andyzhangx))

* fix detach azure disk back off issue which has too big lock in failure retry condition ([#76573](https://github.com/kubernetes/kubernetes/pull/76573), [@andyzhangx](https://github.com/andyzhangx))
* specify azure file share name in azure file plugin ([#76988](https://github.com/kubernetes/kubernetes/pull/76988), [@andyzhangx](https://github.com/andyzhangx))

- Added fields `reason` and `fieldPath` into CRD validation rules to allow users to specify reason and field path when validation failed. ([#118041](https://github.com/kubernetes/kubernetes/pull/118041), [@cici37](https://github.com/cici37)) [SIG API Machinery]