e2e: Use /proc/cmdline instead of rpm-ostree kargs

[cgwalters]

The main motivation here is to work around
coreos/rpm-ostree#3523
(Which is itself a workaround for a RHEL8 systemd bug)

Basically this e2e is invoking rpm-ostree kargs in a pretty
tight loop which triggers that bug.

To read the kernel command line, we can just read /proc/cmdline
instead. (Now, this is the actual cmdline instead of just rpm-ostree's
view of it, but it should be fine)

[cgwalters]

(not tested, but e2e will do that)

[cgwalters]

getKernelArgs and assertKernelArgsEqual are called often from func (c configDriftTest) Run(t *testing.T) {

[cgwalters]

/test e2e-gcp-op

[cgwalters]

/override ci/prow/e2e-aws
/override ci/prow/e2e-agnostic-upgrade
This is a change to our own e2e tests, it can't break cluster installs and testing it is a distracting waste of resources.

[kikisdeliveryservice]

For ref we do exactly this in the actual kargs test:

machine-config-operator/test/e2e/mcd_test.go

Line 148 in 6115967

kargs := helpers.ExecCmdOnNode(t, cs, infraNode, "cat", "/rootfs/proc/cmdline")

/lgtm

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cgwalters, kikisdeliveryservice

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Details

Needs approval from an approver in each of these files:

• OWNERS [cgwalters,kikisdeliveryservice]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[kikisdeliveryservice]

/override ci/prow/e2e-aws
/override ci/prow/e2e-agnostic-upgrade

[openshift-ci]

@kikisdeliveryservice: Overrode contexts on behalf of kikisdeliveryservice: ci/prow/e2e-agnostic-upgrade, ci/prow/e2e-aws

Details

In response to this:

/override ci/prow/e2e-aws
/override ci/prow/e2e-agnostic-upgrade

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[openshift-ci]

@cgwalters: all tests passed!

Full PR test history. Your PR dashboard.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. I understand the commands that are listed here.