The test used to scale the StatefulSet down to 0, wait for ListPods to
return 0 matching Pods, and then scale the StatefulSet back up.

This was prone to a race in which StatefulSet was told to scale back up
before it had observed its own deletion of the last Pod, as evidenced by
logs showing the creation of Pod ss-1 prior to the creation of the
replacement Pod ss-0.

We now wait for the controller to observe all deletions before
scaling it back up. This should fix flakes of the form:

```
Too many pods scheduled, expected 1 got 2
```

Automatic merge from submit-queue (batch tested with PRs 38947, 50239, 51115, 51094, 51116)

Fix comment and typos in node_controller

**What this PR does / why we need it**: 
1. fix comment to more accurately
2. fix typos


**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

**Release note**:

```
NONE
```

Automatic merge from submit-queue (batch tested with PRs 38947, 50239, 51115, 51094, 51116)

update to rbac v1 in bootstrappolicy test

xref https://github.com/kubernetes/features/issues/2



**What this PR does / why we need it**:

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:
cc @liggitt 

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 38947, 50239, 51115, 51094, 51116)

StorageOS: Use VolumeHost.GetExec() to execute stuff in volume plugins

Use VolumeHost.GetExec() to execute stuff in volume plugins

**What this PR does / why we need it**:

This PR updates StorageOS volume plugin to use `VolumeHost.GetExec()` to execute utilities like mkfs and lsblk instead of simple `os/exec`. This prepares the volume plugin to run these utilities in containers instead of running them on the host + makes the volume plugin more independent and less hardcoded.

See proposal in https://github.com/kubernetes/community/pull/589.

Note that this PR does **not** change place where the utilities are executed - `VolumeHost.GetExec()` still leads directly to `os/exec`. It will be changed when the aforementioned proposal is merged and implemented.

@kubernetes/sig-storage-pr-reviews 

**Release note**:
```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 38947, 50239, 51115, 51094, 51116)

Mark the volumes as detached when node does not exist

If node does not exist, node's volumes will be detached
automatically and become available. So mark them detached and do not return err.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
#50200

**Release note**:
```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 38947, 50239, 51115, 51094, 51116)

Call Fatalf instead of Errorf when mounter/unmounter is nil in volume tests

If we get a nil mounter or unmounter, a panic will occur. Should call `Fatalf` instead of `Errorf`.

Automatic merge from submit-queue

Expose detect-project's output in log-dump script

Ref https://github.com/kubernetes/kubernetes/issues/50760

/cc @wojtek-t

Automatic merge from submit-queue (batch tested with PRs 51105, 51097, 51110, 50843, 51107)

gluster: Use VolumeHost.GetExec() to execute stuff in volume plugins

**What this PR does / why we need it**:
This PR updates GlusterFS volume plugin to use `VolumeHost.GetExec()` to execute utilities like mkfs and lsblk instead of simple `os/exec`. This prepares the volume plugin to run these utilities in containers instead of running them on the host + makes the volume plugin more independent and less hardcoded.

See proposal in https://github.com/kubernetes/community/pull/589.

Note that this PR does **not** change place where the utilities are executed - `VolumeHost.GetExec()` still leads directly to `os/exec`. It will be changed when the aforementioned proposal is merged and implemented.

**Special notes for your reviewer**:

There are two commits:
* The first one removes unused `plugin.execCommand` (so we don't need to update it to `VolumeHost.GetExec`)
* The second one does the `VolumeHost.GetExec` trick described above.

@kubernetes/sig-storage-pr-reviews 

**Release note**:
```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 51105, 51097, 51110, 50843, 51107)

FlexVolume: Add ability to control 'SupportsSELinux' during driver's init phase

**What this PR does / why we need it**:
Adds the ability to disable FlexVolume SELinux relabeling for filesystems that don't support it, e.g. fuse

**Which issue this PR fixes**:
This was reported in: https://github.com/lizardfs/lizardfs/issues/581

This is a reworked solution as per feedback from #50548 
https://github.com/kubernetes/kubernetes/pull/50548#issuecomment-322328679

**Special notes for your reviewer**:
/assign @thockin 
/cc @chakri-nelluri @verult @saad-ali 

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 51105, 51097, 51110, 50843, 51107)

nfs: Use VolumeHost.GetExec() to execute stuff in volume plugins

**What this PR does / why we need it**:

This PR updates nfs volume plugin to use `VolumeHost.GetExec()` to execute utilities like mkfs and lsblk instead of simple `os/exec`. This prepares the volume plugin to run these utilities in containers instead of running them on the host + makes the volume plugin more independent and less hardcoded.

See proposal in https://github.com/kubernetes/community/pull/589.

Note that this PR does **not** change place where the utilities are executed - `VolumeHost.GetExec()` still leads directly to `os/exec`. It will be changed when the aforementioned proposal is merged and implemented.

@kubernetes/sig-storage-pr-reviews 

**Release note**:
```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 51105, 51097, 51110, 50843, 51107)

azure: Use VolumeHost.GetExec() to execute stuff in volume plugins

**What this PR does / why we need it**:

This PR updates Azure volume plugin to use `VolumeHost.GetExec()` to execute utilities like mkfs and lsblk instead of simple `os/exec`. This prepares the volume plugin to run these utilities in containers instead of running them on the host + makes the volume plugin more independent and less hardcoded.

See proposal in https://github.com/kubernetes/community/pull/589.

Note that this PR does **not** change place where utilities are executed - `VolumeHost.GetExec()` still leads directly to `os/exec`. It will be changed when the aforementioned proposal is merged and implemented.

To simplify testing, `/sys/bus/scsi/devices/*/model` and `.../vendor` are read using `ioutil.ReadFile` instead of `/bin/cat` in the first commit.

```release-note
NONE
```

@kubernetes/sig-storage-pr-reviews @kubernetes/sig-azure-misc

Automatic merge from submit-queue (batch tested with PRs 51105, 51097, 51110, 50843, 51107)

fibre channel: Remove unused exe interface

**What this PR does / why we need it**:
`execCommand` is not used anywhere, let's remove it and associated `exe` field from several structs.

@kubernetes/sig-storage-pr-reviews 

**Release note**:
```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 50229, 50973, 50976, 51085, 51084)

Correct error strings in glusterfs

Automatic merge from submit-queue (batch tested with PRs 50229, 50973, 50976, 51085, 51084)

Print root cause failure message in StartTestServerOrDie()

**What this PR does / why we need it**:

If the test server cannot be started then print the underling root cause as
opposed to the generic 'Failed to create server chain'.

For example: 

    Failed to create server chain: Model name conflict in merging OpenAPI spec: io.k8s.kube-aggregator.pkg.apis.apiregistration.v1beta1.APIServiceCondition

Automatic merge from submit-queue (batch tested with PRs 50229, 50973, 50976, 51085, 51084)

Small improvements to kubeadm feature-gates

**What this PR does / why we need it**:
This PR implements two small improvements for kubeadm feature-gates:
- Move the generic features package from `cmd/kubeadm/app/cmd/features`to ` cmd/kubeadm/app/features`
- Add CLI flag for `cfg.FeatureFlags`

**Which issue this PR fixes**: 
fixes [#393](https://github.com/kubernetes/kubeadm/issues/393)
fixes [#394](https://github.com/kubernetes/kubeadm/issues/394)

**Special notes for your reviewer**:
Main work of this PR is grouped into two commits, one for each issue + a separated commit for autogenerated bazel files.
cc @luxas 
cc @jamiehannaford

Automatic merge from submit-queue (batch tested with PRs 50229, 50973, 50976, 51085, 51084)

Fix legacy floatingip

Fix #50974
If user specify floating-network-id by annotation rather than cloud
provider file, openstack cloud provider don't delete floatingip when
deleting LoadBalancer service.

**Release note**:
```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 50229, 50973, 50976, 51085, 51084)

Remove duplicate command example

**What this PR does / why we need it**:

`kubectl port-forward --help` currently contains a duplicate example. This PR removes the duplicate.

```release-note
/release-note Remove duplicate command example from `kubectl port-forward --help`
```

/sig cli
/kind cleanup
/kind documentation

Automatic merge from submit-queue (batch tested with PRs 50257, 50247, 50665, 50554, 51077)

fix issue(51027)kubect logs --selector ignoring --tail=-1

**What this PR does / why we need it**:
closes issue #51027 

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

**Release note**:

```release-note
Fix kubect logs --selector ignoring --tail=-1
```

Automatic merge from submit-queue (batch tested with PRs 50257, 50247, 50665, 50554, 51077)

Refactor kubectl factory test case with sets.String

**What this PR does / why we need it**:
change to make got and want use sets.String instead, since that is both safe and more clearly shows the intent.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 50257, 50247, 50665, 50554, 51077)

Replace hard-code "cpu" and "memory" to consts

**What this PR does / why we need it**:
There are many places using hard coded "cpu" and "memory" as resource name. This PR replace them to consts.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:
/kind cleanup

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 50257, 50247, 50665, 50554, 51077)

Add whitespace to improve error msg clarity

**What this PR does / why we need it**:

Currently when `kubectl explain` is called without a resource the error message is tacked onto the end of the list of valid resources. The error is clearer if there is a new line after the valid resource list, this also causes the error to be left aligned instead of indented level with the valid resource list.

```release-note
NONE
```

/sig cli
/kind cleanup

Automatic merge from submit-queue (batch tested with PRs 50257, 50247, 50665, 50554, 51077)

Remove incorrect patch-merge directives.

**What this PR does / why we need it**:

Directives were misplaced for the following types:

- MatchExpressions
- Taints
- Tolerations

Per the discussion in #46547, we cannot fix these because it would cause backwards-compatibility problems. Instead, remove the incorrect ones so they don't mislead users. This has no impact on behavior.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

Takes over from #46547 by @aaronlevy

**Release note**:

```release-note
NONE
```

Automatic merge from submit-queue

Revert "Updated gRPC vendoring to support Keep Alive"

Reverts kubernetes/kubernetes#50531

Ref - https://github.com/kubernetes/kubernetes/issues/51099

/cc @wojtek-t @RenaudWasTaken

Automatic merge from submit-queue (batch tested with PRs 50980, 46902, 51051, 51062, 51020)

fix confusion in service_controller

**What this PR does / why we need it**:

Fix code and comment confusion in `service_controller`.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #51009 

**Special notes for your reviewer**:

**Release note**:

```release-note
```

Automatic merge from submit-queue (batch tested with PRs 50980, 46902, 51051, 51062, 51020)

Fix swallowed errors in statefulset tests

**What this PR does / why we need it**: Fixes errors that were being swallowed in the tests of the statefulset package.

```release-note NONE
```

Automatic merge from submit-queue (batch tested with PRs 50980, 46902, 51051, 51062, 51020)

Fix StatefulSet update validation

StatefulSet update validation did not allow change to number of containers in pod template. Fix this bug so that it's possible to make this kind of change. 

Found it when suggesting test-cmd changes in https://github.com/kubernetes/kubernetes/pull/49674.

@kubernetes/sig-apps-pr-reviews @smarterclayton 

/approve no-issue

Automatic merge from submit-queue (batch tested with PRs 50980, 46902, 51051, 51062, 51020)

Remove seemingly obsolete binaries

It's hard to tell if these are safe to remove.  Let CI tell me.

Automatic merge from submit-queue

kubeadm: Implement 'kubeadm config'

**What this PR does / why we need it**:

Implements a `kubeadm config` command for viewing the current kubeadm configuration stored as a ConfigMap in the cluster and creating that configuration for v1.7- users. kubeadm v1.8+ handles the creation of this ConfigMap at init time, but v1.7 users have to create it themselves with this command in order to be able to preserve the same config after the upgrade.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

fixes: https://github.com/kubernetes/kubeadm/issues/406

**Special notes for your reviewer**:

**Release note**:

```release-note
Adds a new `kubeadm config` command that lets users tell `kubeadm upgrade` what kubeadm configuration to use and lets users view the current state.
```
@kubernetes/sig-cluster-lifecycle-pr-reviews

Automatic merge from submit-queue

Add Humble as GlusterFS approver.

@humblec has shown his commitment into GlusterFS by number of commits there
and by support on sig-storage slack channel.

@kubernetes/sig-storage-misc 

```release-note
NONE
```

Automatic merge from submit-queue (batch tested with PRs 51039, 50512, 50546, 50965, 50467)

add alpha api gate at gce cloud provider

**What this PR does / why we need it**:
Add a flag in gce.conf to gate alpha api. Related wrapper function can choose to examine corresponding gate. 
Currently, there is no new alpha api wrapper funciton being introduced. So there is no supported alpha api.


**Release note**:
```release-note
None
```

cc: @yujuhong @saad-ali @MrHohn

Automatic merge from submit-queue (batch tested with PRs 51039, 50512, 50546, 50965, 50467)

kubeadm: Get kube-dns based on the kubernetes version

**What this PR does / why we need it**:

Makes the kube-dns version used dependent on the kubernetes version. This is required for upgrades as we have to be able to handle one kube-dns version per branch for instance...

Currently a no-op though, as both v1.7 and v1.8 seem to use 1.14.4

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

Dependency for https://github.com/kubernetes/kubernetes/pull/48899 (kubeadm upgrades)

**Release note**:

```release-note
NONE
```
@kubernetes/sig-cluster-lifecycle-pr-reviews 

@kubernetes/dns-maintainers FYI; next time you bump DNS version, please update this func instead of the constant there...

Automatic merge from submit-queue (batch tested with PRs 51039, 50512, 50546, 50965, 50467)

Kubectl: Plumb openapi validation (disabled by default)

**What this PR does / why we need it**: Creates a new flag '--openapi' and plumb in the validation code so that it can be used by default to validate objects against the openapi schema.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: partially https://github.com/kubernetes/kubectl/issues/49

**Special notes for your reviewer**:

This is not complete, the name of the variable must change for example.

**Release note**:
```release-note
Kubectl uses openapi for validation. If OpenAPI is not available on the server, it defaults back to the old Swagger.
```

Automatic merge from submit-queue (batch tested with PRs 51039, 50512, 50546, 50965, 50467)

Add flags for prometheus-to-sd components.

Configure prometheus-to-sd-endpoint and prometheus-to-sd-prefix base on
the environment.

**Release note**:
NONE

Automatic merge from submit-queue

StatefulSet: Deflake e2e "Saturate" phase.

This should reduce one source of flakiness found while investigating #48031.

The "Saturate" phase of StatefulSet e2e tests verifies orderly startup by controlling when each Pod is allowed to report Ready. If a Pod unexepectedly goes down during the test, the replacement Pod
created by the controller will forget if it was already allowed to report Ready.

After this change, the signal that allows each Pod to report Ready is persisted in the Pod's PVC. Thus, the replacement Pod will remember that it was already told to proceed to a Ready state.

Automatic merge from submit-queue (batch tested with PRs 50806, 48789, 49922, 49935, 50438)

kubectl show node role if defined

**What this PR does / why we need it**:

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #50010

**Special notes for your reviewer**:
/assign @justinsb @luxas @jbeda @philips
/cc @qrevel

**Release note**:

```release-note
kubectl show node role if defined
```

Automatic merge from submit-queue (batch tested with PRs 50806, 48789, 49922, 49935, 50438)

Remove deprecated kubectl command aliases

**What this PR does / why we need it**:
These command aliases have been deprecated for more than two years. It's time to remove them.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
ref: #8319 #6118 #8596

**Special notes for your reviewer**:
/sig cli

**Release note**:

```release-note
Remove deprecated kubectl command aliases `apiversions, clusterinfo, resize, rollingupdate, run-container, update`
```