* AWS: Recognize ca-central-1 region ([#38410](https://github.com/kubernetes/kubernetes/pull/38410), [@justinsb](https://github.com/justinsb))
* fix nil dereference when doing a volume type check on persistent volumes ([#39529](https://github.com/kubernetes/kubernetes/pull/39529), [@sjenning](https://github.com/sjenning))

- Omit nil or empty field when calculating container hash value to avoid hash changed. For a new field with a non-nil default value in the container spec, the hash would still get changed. ([#57741](https://github.com/kubernetes/kubernetes/pull/57741), [@dixudx](https://github.com/dixudx))

## Changelog since v1.12.5

### Other notable changes

* kubeadm: fixed nil pointer dereference caused by a bug in url parsing ([#74454](https://github.com/kubernetes/kubernetes/pull/74454), [@bart0sh](https://github.com/bart0sh))

you do this, then, at the time you re-vendor the "<code>k8s.io/kubernetes/"</code> code, you will need to set <code>job.Spec.ManualSelector = true</code>, or else set <code>job.Spec.Selector = nil.  </code>Otherwise, the jobs you create may be rejected.  See [Specifying your own pod selector](http://kubernetes.io/docs/user-guide/jobs/#specifying-your-own-pod-selector).

* Automated cherry pick of [#49259](https://github.com/kubernetes/kubernetes/pull/49259): update json-patch to fix nil value issue when creating mergepatch ([#59324](https://github.com/kubernetes/kubernetes/pull/59324), [@yue9944882](https://github.com/yue9944882))

- Updates that remove remaining `metadata.finalizers` from  an object that is pending deletion (non-nil metadata.deletionTimestamp) and has no graceful deletion pending (nil or 0 metadata.deletionGracePeriodSeconds) now results in immediate deletion of the object. ([#77952](https://github.com/kubernetes/kubernetes/pull/77952), [@liggitt](https://github.com/liggitt))

// so actually
// void atomicload64(uint64 *res, uint64 volatile *addr);
TEXT runtime·atomicload64(SB), NOSPLIT, $0-12
	MOVL	ptr+0(FP), AX
	TESTL	$7, AX
	JZ	2(PC)
	MOVL	0, AX // crash with nil ptr deref
	LEAL	ret_lo+4(FP), BX
	// MOVQ (%EAX), %MM0
	BYTE $0x0f; BYTE $0x6f; BYTE $0x00
	// MOVQ %MM0, 0(%EBX)
	BYTE $0x0f; BYTE $0x7f; BYTE $0x03
	// EMMS
	BYTE $0x0F; BYTE $0x77
	RET

- Fix missing "apiVersion" for "involvedObject" in Events for Nodes. ([#87537](https://github.com/kubernetes/kubernetes/pull/87537), [@uthark](https://github.com/uthark)) [SIG Apps and Node]
- Fix nil pointer dereference in azure cloud provider ([#85975](https://github.com/kubernetes/kubernetes/pull/85975), [@ldx](https://github.com/ldx)) [SIG Cloud Provider]

* Ensure the GCI metadata files do not have newline at the end ([#38727](https://github.com/kubernetes/kubernetes/pull/38727), [@Amey-D](https://github.com/Amey-D))
* Fix nil pointer dereference in test framework ([#37583](https://github.com/kubernetes/kubernetes/pull/37583), [@mtaufen](https://github.com/mtaufen))

- A customizable `OrderedScoreFuncs()` function was introduced. Out-of-tree plugins 
  that used the scheduler's preemption interface could implement this function
  for custom preemption preferences or return nil to keep the current behavior. ([#121867](https://github.com/kubernetes/kubernetes/pull/121867), [@lianghao208](https://github.com/lianghao208))