ci: teach actionlint the ubuntu-26.04 runner labels

[jamesarich]

Why

main is red, and every branch cut from it inherits the failure.

The runners moved to ubuntu-26.04 / ubuntu-26.04-arm, but the actionlint pinned in pull-request.yml:290 is 1.7.12, which does not know those labels. It reports 26 unknown-label findings across 20 workflow files and fails Check Store Metadata → Lint GitHub workflows (actionlint).

The step lints the whole directory, so this fails on PRs that touch no workflow at all:

14 × label "ubuntu-26.04-arm" is unknown
12 × label "ubuntu-26.04" is unknown

.github/actionlint.yaml did not exist.

Why not just bump actionlint

Checked, and there is nothing to bump to:

• 1.7.12 is the latest release (published 2026-03-30). The pin is already current.
• main upstream doesn't know the label either — rule_runner_label.go lists only ubuntu-22.04, ubuntu-22.04-arm, ubuntu-24.04, ubuntu-24.04-arm. Building from HEAD would not help.
• Three open upstream issues, none merged: #723, #683, #682.

So this config is the only available fix until upstream lands support.

🛠️ Build

• Add .github/actionlint.yaml declaring the two labels.

The key is named self-hosted-runner, but these are ordinary GitHub-hosted runners — it is simply actionlint's only mechanism for teaching it a label it doesn't know. Noted in a comment, with the removal condition.

Testing Performed

Reproduced with the exact version CI installs (download-actionlint.bash 1.7.12):

	findings	exit
origin/main (8f1f1392c), extracted clean	26	1
this branch	0	0

It does not disable the check. With the config in place, substituting a made-up label is still reported:

label "totally-made-up-runner" is unknown

The allowance is scoped to the two labels actually in use.

Note

Found while diagnosing a failure on #7221, which I first assumed was mine — it wasn't. Every other open PR in the repo is failing the same way, so this unblocks them too.

Summary by CodeRabbit

• Chores
  • Updated workflow validation to recognize additional Ubuntu 26.04 runner labels.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Advanced

Run ID: 02ed6f0d-bb54-46a6-9343-efca52dd6627

📥 Commits

Reviewing files that changed from the base of the PR and between 8f1f139 and e1aa427.

📒 Files selected for processing (1)

• .github/actionlint.yaml

Included review availability: Your plan provides up to 4 included reviews per hour; 0 remain after this review.

---

📝 Walkthrough

Walkthrough

The pull request adds an actionlint configuration file. It registers ubuntu-26.04 and ubuntu-26.04-arm as recognized self-hosted-runner labels.

Changes

Actionlint runner label configuration

Layer / File(s)	Summary
Register Ubuntu 26.04 runner labels .github/actionlint.yaml	The configuration adds ubuntu-26.04 and ubuntu-26.04-arm under self-hosted-runner labels.

Priority: ⬇️ Low

Estimated code review effort: 1 (Trivial) | ~5 minutes

Change: Bug fix

Merge Risk: ⚪ Minimal · up to e1aa4

This change should allow the intended Ubuntu 26.04 runner labels without introducing a material merge risk.

🚥 Pre-merge checks | ✅ 8

✅ Passed checks (8 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Sibling Call Sites And Presence Semantics	✅ Passed	PASS. The review-scoped diff changes only .github/actionlint.yaml and adds actionlint runner-label configuration. It does not change a field representation, a zero guard, a presence check, a default…
Tests Prove The Path, Not The End State	✅ Passed	PASS: The authoritative pull-request diff contains only one added configuration file, .github/actionlint.yaml. It adds no test or test-like file and changes no test declarations. Therefore, the cust…
Regression Coverage For Changed Behavior	✅ Passed	No coverage gap is introduced. The pull request changes only .github/actionlint.yaml, a CI lint configuration; it does not change application code or any listed runtime surface. The existing `Lint G…
Moved Code Diffed Against Its Original	✅ Passed	PASS: The review-scoped diff changes only one file, .github/actionlint.yaml, and adds 10 configuration/comment lines. It deletes no type or function and does not extract code into another file or mo…
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: configuring actionlint to recognize the Ubuntu 26.04 runner labels.

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}