📖 backport policy: Add go version bumps

[sbueringer]

Signed-off-by: Stefan Büringer buringerst@vmware.com

What this PR does / why we need it:

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
For context, please see #7974

[sbueringer]

cc @fabriziopandini @CecileRobertMichon @vincepri @enxebre
cc @kubernetes-sigs/cluster-api-release-team

[killianmuldoon]

/lgtm

Seems reasonable to leave the conditions for this up to a case-by-case basis - especially depending on go version change impact, and how long the release is going to stay supported i.e. 2 months vs 2 days.

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 41e5bbbdeddf416733ce4ddc17192d43f720ae95

[sbueringer]

Seems reasonable to leave the conditions for this up to a case-by-case basis - especially depending on go version change impact, and how long the release is going to stay supported i.e. 2 months vs 2 days.

Yup. I think we can see how it goes the first few times.

It might depend on the exact changes in Go, but I think in almost all cases it shouldn't actually affect folks importing Cluster API when we only bump the version we compile with (it should not be strictly necessary to bump the version in go.mod, xref: #7974 (comment)). The only reason to bump the go.mod version would be to force consumers to compile with a newer Go minor version (e.g. to enforce that they pick up CVE fixes), although we can't enforce a specific patch version that way. But we can discuss and decide this when we get there.

Bumping the Go version we compile with might have impact on folks using our published images though. For example changes in garbage collector behavior etc., like mentioned in the upstream mail:

"We paid special attention to preserving existing behavior for 1.23 and 1.24. For example, on the release-1.23 branch, we overrode some of the garbage collector changes in Go 1.19 that might affect kube-apiserver resource consumption to match Go 1.17 defaults (for more information on that specific change, see the Kubernetes 1.24 release note[1] about GOGC tuning on Go 1.18+.".

[ykakarap]

This is primarily to keep the patch version up to date, right? If so, can we make that explicit that this item is only to update the patch version and not the minor version.

The minor version is updated during Kubernetes bump and not here, isn't it?

[sbueringer]

In most cases patch

Sometimes

Note: If the Go minor version of one of our supported branches goes out of supported, we should consider bumping
to a newer Go minor version according to our backport policy.

[sbueringer]

Kubernetes bump never bumps the go version on release branches as that part of the work is only done on main

[fabriziopandini]

/lgtm

[vincepri]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: vincepri

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

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [vincepri]

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

[sbueringer]

/cherry-pick release-1.3

[k8s-infra-cherrypick-robot]

@sbueringer: new pull request created: #8115

In response to this:

/cherry-pick release-1.3

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.