Run ARM64 tests in CI

.github/workflows/env/action.yml

@@ -5,11 +5,42 @@ runs:
   steps:
     - name: Install dependencies
       shell: bash
-      run: sudo apt-get install -y llvm clang dwz cmake curl unzip
-    - name: Set up Go ${{matrix.go}}
+      run: |
+        # Ubuntu has ARM64 packages in an entirely different repo, so we can't just
+        # `dpkg --add-architecture arm64` here: we have to add a custom sources.list first.
+        sudo tee /etc/apt/sources.list.d/ubuntu.sources <<EOF > /dev/null
+        #
+        # AMD64
+        #
+      
+        Types: deb
+        URIs: http://azure.archive.ubuntu.com/ubuntu/
+        Suites: noble noble-updates noble-backports
+        Components: main universe restricted multiverse
+        Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+        Architectures: amd64
+        
+        #
+        # ARM64
+        #
+      
+        Types: deb
+        URIs: http://azure.ports.ubuntu.com/ubuntu-ports/
+        Suites: noble noble-updates noble-backports
+        Components: main universe restricted multiverse
+        Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+        Architectures: arm64
+        EOF
+        
+        sudo dpkg --add-architecture arm64
+        sudo apt-get update -y
+        
+        sudo apt-get install -y llvm clang dwz curl unzip gcc-aarch64-linux-gnu \
+          libc6-arm64-cross qemu-user-binfmt libc6:arm64
+    - name: Set up Go ${{ matrix.go }}
       uses: actions/setup-go@v5
       with:
-        go-version: ${{matrix.go}}
+        go-version: ${{ matrix.go }}
         check-latest: true
         cache-dependency-path: go.sum
       id: go

.github/workflows/unit-test-on-pull-request.yml

@@ -34,14 +34,20 @@ jobs:
       max-parallel: 2
       matrix:
         go: ["stable"]
+        toolchain:
+          - { goarch: amd64, cc: gcc }
+          - { goarch: arm64, cc: aarch64-linux-gnu-gcc }
     steps:
       - name: Clone code
         uses: actions/checkout@v4
       - name: Set up environment
         uses: ./.github/workflows/env
       - name: Build
         run: |
-          echo $PATH
+          export GOARCH=${{ matrix.toolchain.goarch }} 
+          export CC=${{ matrix.toolchain.cc }} 
+          export OBJCOPY=llvm-objcopy # works cross-arch
+          export CGO_ENABLED=1
           make test
       - name: Tests
         run: |
@@ -51,18 +57,28 @@ jobs:
     name: Build integration test binaries
     runs-on: ubuntu-24.04
     timeout-minutes: 10
+    strategy:
+      matrix:
+        toolchain:
+          - { goarch: amd64, cc: gcc }
+          - { goarch: arm64, cc: aarch64-linux-gnu-gcc }
     steps:
       - name: Clone code
         uses: actions/checkout@v4
       - name: Set up environment
         uses: ./.github/workflows/env
       - name: Prepare integration test binaries for qemu tests
         run: |
+          export GOARCH=${{ matrix.toolchain.goarch }} 
+          export CC=${{ matrix.toolchain.cc }} 
+          export OBJCOPY=llvm-objcopy # works cross-arch
+          export CGO_ENABLED=1
           make integration-test-binaries
+
       - name: Upload integration test binaries
         uses: actions/upload-artifact@v4
         with:
-          name: integration-test-binaries
+          name: integration-test-binaries-${{ matrix.toolchain.goarch }}
           path: support/*.test
 
   integration-tests:
@@ -71,6 +87,9 @@ jobs:
     needs: build-integration-test-binaries
     strategy:
       matrix:
+        toolchain:
+          - { arch: x86, goarch: amd64, cc: gcc }
+          - { arch: aarch64, goarch: arm64, cc: aarch64-linux-gnu-gcc }
         kernel-version:
           - "4.19.314"
           - "5.4.276"
@@ -87,19 +106,21 @@ jobs:
         uses: ./.github/workflows/env
       - name: Install dependencies
         run: |
-          sudo apt-get -y install qemu-system-x86
+          sudo apt-get -y install qemu-system-${{ matrix.toolchain.arch }}
           go install github.com/florianl/[email protected]
           sudo mv ~/go/bin/bluebox /usr/local/bin/.
       - name: Fetch integration test binaries
         uses: actions/download-artifact@v4
-        with: { name: integration-test-binaries }
+        with: { name: integration-test-binaries-${{ matrix.toolchain.goarch }} }
       - name: Fetch precompiled kernels
         run: |
           install -d ci-kernels
           echo "FROM ghcr.io/cilium/ci-kernels:${{ matrix.kernel-version }}" \
-            | docker buildx build --quiet --pull --output="ci-kernels" -
+            | docker buildx build --platform linux/${{ matrix.toolchain.goarch }} \
+              --quiet --pull --output="ci-kernels" -
           mv ci-kernels/boot/ ci-kernels/${{ matrix.kernel-version }}/
       - name: Test on kernel ${{ matrix.kernel-version }}
         run: |
           chmod a+rx *.test
+          export QEMU_ARCH=${{ matrix.toolchain.arch}}
           support/run-tests.sh ${{ matrix.kernel-version }}

libpf/pfelf/testdata/Makefile

@@ -1,5 +1,8 @@
 .PHONY: all
 
+CC ?= cc
+OBJCOPY ?= objcopy
+
 BINARIES=fixed-address \
 	go-binary \
 	kernel-image \
@@ -15,18 +18,18 @@ clean:
 	rm -f $(BINARIES)
 
 with-debug-syms: test.c
-	gcc $< -g -o $@
+	$(CC) $< -g -o $@
 
 without-debug-syms: test.c
-	gcc $< -s -o $@
+	$(CC) $< -s -o $@
 
 separate-debug-file: with-debug-syms
-	objcopy --only-keep-debug $< $@
+	$(OBJCOPY) --only-keep-debug $< $@
 
 fixed-address: fixed-address.c fixed-address.ld
 	# The following command will likely print a warning (about a missing -T option), which should be ignored.
 	# Removing the warning would require passing a fully-fledged linker script to bypass gcc's default.
-	gcc $^ -o $@
+	$(CC) $^ -o $@
 
 # Write an ELF notes file with a build ID
 the_notorious_build_id:
@@ -36,12 +39,12 @@ the_notorious_build_id:
 	bash -c "echo -en 'somedata\x04\x00\x00\x00\x14\x00\x00\x00\x03\x00\x00\x00GNU\x00_notorious_build_id_\x00somedata' > $@"
 
 kernel-image: test.c
-	gcc $< -s -o $@ -DLINUX_VERSION="\"Linux version 1.2.3\\n\""
+	$(CC) $< -s -o $@ -DLINUX_VERSION="\"Linux version 1.2.3\\n\""
 
 ubuntu-kernel-image: test.c
-	gcc $< -s -o $@ -DLINUX_VERSION="\"Linux version 1.2.3 (Ubuntu 4.5.6)\\n\""
+	$(CC) $< -s -o $@ -DLINUX_VERSION="\"Linux version 1.2.3 (Ubuntu 4.5.6)\\n\""
 
 # A fake go binary (with a .gopclntab section)
 go-binary: without-debug-syms
-	objcopy --add-section .gopclntab=/dev/null $< $@
+	$(OBJCOPY) --add-section .gopclntab=/dev/null $< $@
 

reporter/testdata/Makefile

@@ -1,7 +1,7 @@
 .PHONY: all
 
-CC=gcc
-CFLAGS=-Wl,--build-id
+CC ?= cc
+CFLAGS = -Wl,--build-id
 
 all: test
 

support/run-tests.sh

@@ -1,10 +1,11 @@
 #!/usr/bin/env bash
 # Test the current package under a different kernel.
-# Requires qemu-system-x86_64 and bluebox to be installed.
+# Requires qemu-system-$QEMU_ARCH and bluebox to be installed.
 
 set -eu
 set -o pipefail
 
+qemu_arch="${QEMU_ARCH:-x86_64}"
 color_green=$'\033[32m'
 color_red=$'\033[31m'
 color_default=$'\033[39m'
@@ -48,7 +49,7 @@ fi
 bluebox "${bb_args[@]}" || (echo "failed to generate initramfs"; exit 1)
 
 echo Testing on "${kernel_version}"
-$sudo qemu-system-x86_64 ${additionalQemuArgs} \
+$sudo qemu-system-${qemu_arch} ${additionalQemuArgs} \
 	-nographic \
 	-append "console=ttyS0" \
 	-monitor none \

tools/fake-apm-agent/Makefile

@@ -1,5 +1,7 @@
 .PHONY: clean all
 
+CC ?= cc
+
 ARCH=$(shell uname -m)
 LIB_NAME=elastic-jvmti-linux-$(ARCH).so
 
@@ -12,10 +14,10 @@ endif
 all: fake-apm-agent $(LIB_NAME)
 
 $(LIB_NAME): fake-apm-agent-lib.c
-	cc $< -g -shared -fPIC -mtls-dialect=$(TLS_DIALECT) -ftls-model=global-dynamic -o $@
+	$(CC) $< -g -shared -fPIC -mtls-dialect=$(TLS_DIALECT) -ftls-model=global-dynamic -o $@
 
 fake-apm-agent: fake-apm-agent.c
-	cc $< -g -DLIB_NAME='"$(LIB_NAME)"' -o $@
+	$(CC) $< -g -DLIB_NAME='"$(LIB_NAME)"' -o $@
 
 clean:
 	rm elastic-jvmti-linux-$(ARCH).so