kubeadm: Support >= 5.0 Linux kernel

[brb]

What type of PR is this?

/kind feature

What this PR does / why we need it:

This PR makes kubeadm preflight checks to work with Linux kernel >= 5.0. The checks currently fail when running on the >= 5.0 kernel:

# kubeadm init
<..>
[ERROR SystemVerification]: unsupported kernel release: 5.0.0-rc6+
<..>

Does this PR introduce a user-facing change?:

kubeadm: Do not fail preflight checks when running on >= 5.0 Linux kernel

[k8s-ci-robot]

Hi @brb. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[neolit123]

this looks like a valid change. thanks @brb
/priority important-longterm
/approve
/ok-to-test

@kubernetes/sig-cluster-lifecycle-pr-reviews

[detiber]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: brb, neolit123

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• cmd/kubeadm/OWNERS [neolit123]

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[jirislaby]

This test is completely bogus. Are you willing to update this with every kernel update? The numbering scheme has changed and the pace will be much higher exactly due to tests like these.

So please either drop the test completely or make it something really general like [4-9].., [1-9][0-9]..

[neolit123]

@jirislaby
are you willing to send a PR? we need to support 3.10+

[mqasimsarfraz]

Would it be a good idea have this back ported at least on 1.13.X ?#75437

[neolit123]

commented on the PR:
#75437 (comment)