Add (refactor) workflow for building gvltctl and tesing VM builder

.github/workflows/vm_build.yaml

@@ -1,33 +1,125 @@
-name: Test Linux VM build
+name: Build and test
 
-# For now triggers only manually, because it takes a lot of time to run this (to build Linux kernel actually).
 on:
   workflow_dispatch:
+  pull_request:
+  push:
+    branches:
+      - main
+    tags:
+      - "*"
 
 jobs:
-  check:
-    runs-on: ubuntu-latest
+  build-gvltctl:
+    name: Build gvltctl
+
+    # Matches test-vm-builder to avoid errors
+    runs-on: ubuntu-24.04
+
+    steps:
+      - name: Checkout sources
+        uses: actions/checkout@v4
+
+      - name: Update APT packages
+        run: |-
+          sudo apt-get update
+
+      - name: Install Buf
+        uses: bufbuild/buf-setup-action@v1
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Install Protoc
+        uses: arduino/setup-protoc@v3
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Install Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          default: true
+
+      - name: Use Rust cache
+        uses: Swatinem/rust-cache@v2
+
+      - name: Build gvltctl
+        run: |-
+          cargo build --features vm-builder-v2
+          cp target/debug/gvltctl .
+
+      - name: Upload build artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: gvltctl-exe
+          path: gvltctl
+          retention-days: 1
+          if-no-files-found: error
+          overwrite: true
+
+  test-vm-builder:
+    name: Test VM builder
+
+    needs: [build-gvltctl]
+
+    # It's important to run on Ubuntu 24, not Ubuntu 22, because
+    # fuse2fs is required to be >=1.47 and Ubuntu 22 only has 1.46.
+    runs-on: ubuntu-24.04
+
     steps:
       - name: Checkout sources
         uses: actions/checkout@v4
 
-      - name: Install Podman
+      - name: Download gvltctl
+        uses: actions/download-artifact@v4
+        with:
+          name: gvltctl-exe
+          path: tests/vm_builder/simple_vm
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Update APT packages
         run: |-
           sudo apt-get update
-          sudo apt-get install -y podman
 
-      - name: Build gvltctl debug container (with vm-builder-v2)
+      - name: Install gvltctl runtime dependencies
         run: |-
-          podman build -t gvltctl:latest -f containers/Containerfile.debug-test-vm-builder-v2 .
+          sudo apt-get install -y ca-certificates
 
-      - name: Run Linux VM builder
+      # We are using pre-compiled kernel in tests, so we don't need Linux kernel build dependencies.
+      - name: Install VM builder runtime dependencies
         run: |-
-          podman run --privileged --rm \
-            -e RUST_LOG=trace \
-            -v ${{ github.workspace }}/tests/vm_builder/simple_vm:/mnt/simple_vm \
-            -w /mnt/simple_vm \
-            gvltctl:latest build --fuse -f Containerfile --no-gevulot-runtime
+          sudo apt-get install -y podman e2fsprogs fuse2fs
 
-      - name: Check disk.img
+      - name: Install QEMU
+        run: |-
+          sudo apt-get install -y qemu-system-x86
+
+      - name: Build test VM image
+        working-directory: tests/vm_builder/simple_vm
+        env:
+          RUST_LOG: trace
+        run: |-
+          chmod +x ./gvltctl
+          ./gvltctl build \
+            --fuse \
+            --containerfile Containerfile \
+            --kernel-file bin/bzImage \
+            --no-gevulot-runtime
+
+      - name: Check disk.img file
+        working-directory: tests/vm_builder/simple_vm
         run: |-
           file disk.img
+
+      - name: Run test VM
+        working-directory: tests/vm_builder/simple_vm
+        run: |-
+          OUTPUT=$(qemu-system-x86_64 -machine q35 -nographic --hda disk.img)
+          echo "$OUTPUT"
+          RES=$(echo "$OUTPUT" | grep "Hello, world!")
+          if [[ $RES = "" ]]; then
+              echo "FAILED"
+              exit 1;
+          else
+              echo "OK"
+          fi