of the beta plugin registration directory `{kubelet_root_dir}/plugins/` for registration of external drivers via the kubelet plugin registration protocol is deprecated in favor of `{kubelet_root_dir}/plugins_registry/`. Support for the old directory is planned to be removed in v1.15. Device plugin and CSI storage drivers should switch to the new directory prior to v1.15. Only CSI storage drivers that support 0.x versions of the CSI API are allowed in the old directory. ([#70494](https://github.c...

- Some of the in-tree storage drivers indicate support for the `MetricsProvider` interface, but fail to configure this for BlockMode volumes. With a recent change, `Kubelet` will call `GetMetrics()` for BlockMode volumes, and the in-tree drivers that miss the support cause a Go panic. Now the in-tree storage drivers that support BlockMode volumes, will return the Capacity of the volume in the `GetMetrics()` call. ([#1015...

### Security Improvements for CSI Drivers (Alpha)

    - [Skip Volume Ownership change graduates to GA](#skip-volume-ownership-change-graduates-to-ga)
    - [Allow CSI drivers to opt-in to volume ownership and permission change graduates to GA](#allow-csi-drivers-to-opt-in-to-volume-ownership-and-permission-change-graduates-to-ga)
    - [PodSecurity graduates to Beta](#podsecurity-graduates-to-beta)

### Bug or Regression

- Aggregate errors when putting vmss
  fix: consolidate logs for instance not found error (#105365, @nilo19) [SIG Cloud Provider]
- Allow CSI drivers to just run offline expansion tests (#102740, @gnufied) [SIG Storage and Testing]

- This release added support for `NodeExpandSecret` for CSI driver client which enables the CSI drivers to make use of this secret while performing node expansion operation based on the user request. Previously there was no secret  provided as part of the `nodeexpansion` call, thus CSI drivers did not make use of the same while expanding the volume at the node side. ([#105963](https://github.com/kubernetes/kubernetes/pull/105963), [@zhucan](...

#### **Other**

*   Pod Security Policy can now manage access to specific FlexVolume drivers ([#53179](https://github.com/kubernetes/kubernetes/pull/53179),[ @wanghaoran1988](https://github.com/wanghaoran1988))

- `CSINodeExpandSecret` feature has been promoted to `GA` in this release and is enabled
  by default. The CSI drivers can make use of the `secretRef` values passed in `NodeExpansion`

* Bug fixes

  * Fixes issue with Flexvolume, introduced in 1.6.0, where drivers without an attacher would fail (node indefinitely waiting for attach). A driver API addition is introduced: drivers that don't implement attach should return attach: false on init. ([#47503](https://github.com/kubernetes/kubernetes/pull/47503), [@chakri-nelluri](https://github.com/chakri-nelluri))

    * ACTION REQUIRED: the alpha CRDs are no longer used and drivers will need to be updated to use the beta APIs.
    * The support for `_` in the CSI driver name will be dropped as the CSI Spec does not allow that. 

### Other notable changes