ci: don't install private golangci-lint; bump to v2.4

[kolyshkin]

First, let's not install golangci-lint from Makefile, instead relying on whatever version a developer already has installed and available.

Second, we still need golangci-lint in GHA CI. For that, let's use golangci-lint-action. Unfortunately, there's no way to NOT run it from the action, or run it on multiple directories (see 1), so run it on a single module.

This is better for CI because we use all the good bits from the golangci-lint-action (caching and annotations).

While at it, bump golangci-lint from v2.0.3 to v2.4.x.

[kolyshkin]

OK, it works like expected:

• cache is saved
• annotations are shown (albeit there are multiple ones since our matrix is big)

[Copilot]

Pull Request Overview

This PR modernizes the golangci-lint setup by removing local installation from the Makefile and updating the CI configuration to use the official golangci-lint GitHub Action. The changes also bump the golangci-lint version from v2.0.2 to v2.4.

• Removes private golangci-lint installation logic from Makefile, expecting developers to have it pre-installed
• Adds golangci-lint-action to GitHub Actions workflow for better CI integration with caching and annotations
• Updates golangci-lint version from v2.0.2 to v2.4

Reviewed Changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated no comments.

File	Description
Makefile	Removes BINDIR variable and golangci-lint installation targets, simplifies lint command to use system-installed golangci-lint
.github/workflows/test.yml	Adds golangci-lint-action step with v2.4 version targeting reexec module

---

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[thaJeztah]

Perhaps would be nice to have an early fail; currently this shows;

docker run -it --rm -v ./:/sys -w /sys golang:1.24 make lint
set -eu; \
for p in atomicwriter capability mountinfo mount reexec sequential signal symlink user userns ; do \
	(cd $p; go mod download; golangci-lint run;) \
done
/bin/sh: 3: golangci-lint: not found
make: *** [Makefile:18: foreach] Error 127

If we add a step before foreach, we can fail before that output;

.PHONY: check-golangci
check-golangci:
	@command -v golangci-lint >/dev/null 2>&1 || { echo "golangci-lint is not installed"; exit 1; }
	@golangci-lint version

.PHONY: lint
lint: check-golangci
lint: CMD=go mod download; golangci-lint run
lint: foreach

docker run -it --rm -v ./:/sys -w /sys golang:1.24 make lint
golangci-lint is not installed
make: *** [Makefile:51: check-golangci] Error 1

And after installing;

docker run -it --rm -v ./:/sys -w /sys golang:1.24
curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/HEAD/install.sh | sh -s -- -b $(go env GOPATH)/bin v2.4.0
make lint
golangci-lint has version 2.4.0 built with go1.25.0 from 43d03392 on 2025-08-13T23:36:29Z
set -eu; \
for p in atomicwriter capability mountinfo mount reexec sequential signal symlink user userns ; do \
	(cd $p; go mod download; golangci-lint run;) \
done

[kolyshkin]

Perhaps would be nice to have an early fail

Good idea; I've simplified this to:

--- a/Makefile
+++ b/Makefile
@@ -46,11 +46,14 @@ test-local:
        cd atomicwriter && go mod tidy $(MOD) && go test $(MOD) $(RUN_VIA_SUDO) -v .
        $(RM) atomicwriter/go-local.*
 
+.PHONY: golangci-lint-version
+golangci-lint-version:
+       golangci-lint version
+
 .PHONY: lint
+lint: golangci-lint-version
 lint: CMD=go mod download; golangci-lint run
 lint: foreach
-lint:
-       golangci-lint version
 
 .PHONY: cross
 cross:

which results in a similar effect (slightly different but clear enough error message):

[kir@kir-tp1 sys]$ podman run -it --rm -v ./:/sys -w /sys golang:1.24 make lint
golangci-lint version
make: golangci-lint: No such file or directory
make: *** [Makefile:51: golangci-lint-version] Error 127

[kolyshkin]

PR updated; PTAL @thaJeztah

[thaJeztah]

which results in a similar effect (slightly different but clear enough error message):

Works for me; good enough!

[thaJeztah]

LOL, I initially had that, then went looking to make it nicer, but agreed; let's not complicate things. What works, works (and most users of this repo should probably be able to deduct what's happening!)

[thaJeztah]

LGTM