- Added `SchedulerPopFromBackoffQ` feature gate that is in beta and enabled by default. Improved scheduling queue behavior by popping pods from the backoffQ when the activeQ is empty. This allows to process potentially schedulable pods ASAP, eliminating a penalty effect of the backoff queue. ([#130772](https://github.com/kubernetes/kubernetes/pull/130772), [@macsko](https://github.com/macsko))...

The Kubernetes in-tree storage plugin to Container Storage Interface (CSI) migration infrastructure is now beta in Kubernetes v1.17. CSI migration was introduced as alpha in Kubernetes v1.14.

## Known Issues
- volumeDevices mapping ignored when container is privileged

- Port mapping now allows the same `containerPort` of different containers to different `hostPort` without naming the mapping explicitly. ([#94494](https://github.com/kubernetes/kubernetes/pull/94494), [@SergeyKanzhelev](https://github.com/SergeyKanzhelev))

- kubectl supports copying files with wild card ([#72641](https://github.com/kubernetes/kubernetes/pull/72641), [@dixudx](https://github.com/dixudx))

- Improved memory usage of `kube-scheduler` by dropping the `.metadata.managedFields` field that `kube-scheduler` doesn't require. ([#119556](https://github.com/kubernetes/kubernetes/pull/119556), [@linxiulei](https://github.com/linxiulei))

* Added a new `kubeadm upgrade node config` command. ([#64624](https://github.com/kubernetes/kubernetes/pull/64624), [@luxas](https://github.com/luxas))
* kubeadm now makes the CoreDNS container more secure by dropping (root) capabilities and improves the integrity of the container by running the whole container in read-only.  ([#64473](https://github.com/kubernetes/kubernetes/pull/64473), [@nberlee](https://github.com/nberlee))

Initially, the bound type parameters are known but the map is empty.
During type unification, if a new type argument <code>A</code> is inferred,
the respective mapping <code>P ➞ A</code> from type parameter to argument
is added to the map.
Conversely, when comparing types, a known type argument
(a type argument for which a map entry already exists)

* [fluentd-gcp addon] Fluentd will trim lines exceeding 100KB instead of dropping them. ([#52289](https://github.com/kubernetes/kubernetes/pull/52289), [@crassirostris](https://github.com/crassirostris))

  for the service, but there is at least one Terminating pod for that service on the node,
  then kube-proxy will send the traffic to the Terminating pod rather than dropping it. This
  patches up a race condition between when a pod is killed and when the external load

* Add limitrange/resourcequota/downward_api  e2e tests for local ephemeral storage ([#52523](https://github.com/kubernetes/kubernetes/pull/52523), [@NickrenREN](https://github.com/NickrenREN))
* Support copying "options" in resolv.conf into pod sandbox when dnsPolicy is Default ([#54773](https://github.com/kubernetes/kubernetes/pull/54773), [@phsiao](https://github.com/phsiao))