Add Azure Linux 4.0 support

.github/workflows/build.yml

@@ -45,51 +45,103 @@ jobs:
     permissions:
       contents: read
 
-  tests-functional-azl-on-azl3-amd64:
-    name: Functional tests AZL on AZL3 AMD64
+  tests-functional-azl3-on-azl3-amd64:
+    name: Functional tests AZL3 on AZL3 AMD64
     if: ${{ inputs.runFunctionalTests }}
     uses: ./.github/workflows/tests-functional.yml
     with:
-      testDistro: azl
+      testDistro: azl3
       hostDistro: azl3
       hostArch: amd64
     permissions:
       contents: read
       # Azure login.
       id-token: write
 
-  tests-functional-azl-on-azl3-arm64:
-    name: Functional tests AZL on AZL3 ARM64
+  tests-functional-azl4-on-azl3-amd64:
+    name: Functional tests AZL4 on AZL3 AMD64
     if: ${{ inputs.runFunctionalTests }}
     uses: ./.github/workflows/tests-functional.yml
     with:
-      testDistro: azl
+      testDistro: azl4
+      hostDistro: azl3
+      hostArch: amd64
+    permissions:
+      contents: read
+      # Azure login.
+      id-token: write
+
+  tests-functional-azl3-on-azl3-arm64:
+    name: Functional tests AZL3 on AZL3 ARM64
+    if: ${{ inputs.runFunctionalTests }}
+    uses: ./.github/workflows/tests-functional.yml
+    with:
+      testDistro: azl3
+      hostDistro: azl3
+      hostArch: arm64
+    permissions:
+      contents: read
+      # Azure login.
+      id-token: write
+
+  tests-functional-azl4-on-azl3-arm64:
+    name: Functional tests AZL4 on AZL3 ARM64
+    if: ${{ inputs.runFunctionalTests }}
+    uses: ./.github/workflows/tests-functional.yml
+    with:
+      testDistro: azl4
       hostDistro: azl3
       hostArch: arm64
     permissions:
       contents: read
       # Azure login.
       id-token: write
 
-  tests-functional-azl-on-ubuntu2404-amd64:
-    name: Functional tests AZL on Ubuntu24.04 AMD64
+  tests-functional-azl3-on-ubuntu2404-amd64:
+    name: Functional tests AZL3 on Ubuntu24.04 AMD64
     if: ${{ inputs.runFunctionalTests }}
     uses: ./.github/workflows/tests-functional.yml
     with:
-      testDistro: azl
+      testDistro: azl3
       hostDistro: ubuntu2404
       hostArch: amd64
     permissions:
       contents: read
       # Azure login.
       id-token: write
 
-  tests-functional-azl-on-ubuntu2404-arm64:
-    name: Functional tests AZL on Ubuntu24.04 ARM64
+  tests-functional-azl4-on-ubuntu2404-amd64:
+    name: Functional tests AZL4 on Ubuntu24.04 AMD64
+    if: ${{ inputs.runFunctionalTests }}
+    uses: ./.github/workflows/tests-functional.yml
+    with:
+      testDistro: azl4
+      hostDistro: ubuntu2404
+      hostArch: amd64
+    permissions:
+      contents: read
+      # Azure login.
+      id-token: write
+
+  tests-functional-azl3-on-ubuntu2404-arm64:
+    name: Functional tests AZL3 on Ubuntu24.04 ARM64
+    if: ${{ inputs.runFunctionalTests }}
+    uses: ./.github/workflows/tests-functional.yml
+    with:
+      testDistro: azl3
+      hostDistro: ubuntu2404
+      hostArch: arm64
+    permissions:
+      contents: read
+      # Azure login.
+      id-token: write
+
+  tests-functional-azl4-on-ubuntu2404-arm64:
+    name: Functional tests AZL4 on Ubuntu24.04 ARM64
     if: ${{ inputs.runFunctionalTests }}
     uses: ./.github/workflows/tests-functional.yml
     with:
-      testDistro: azl
+      testDistro: azl4
       hostDistro: ubuntu2404
       hostArch: arm64
     permissions:

.github/workflows/scripts/ukify-fix-insertion-of-padding-in-merged-sections.patch

@@ -0,0 +1,30 @@
+From c66a29f6f7b070bc653bce88e14fc5296e226768 Mon Sep 17 00:00:00 2001
+From: Vince Perri <5596945+vinceaperri@users.noreply.github.com>
+Date: Tue, 21 Apr 2026 22:46:42 +0000
+Subject: [PATCH] ukify: fix insertion of padding in merged sections
+
+Original patch:
+https://github.com/systemd/systemd/commit/ec1d031f3de02f84beca89e2b402d085fba62be4
+
+---
+ ukify | 3 +--
+ 1 file changed, 1 insertion(+), 2 deletions(-)
+
+diff --git a/ukify b/ukify
+index 7f9d6e6..232ebe4 100755
+--- a/ukify
++++ b/ukify
+@@ -618,9 +618,8 @@ def pe_add_sections(uki: UKI, output: str):
+                 if new_section.Misc_VirtualSize > s.SizeOfRawData:
+                     raise PEError(f'Not enough space in existing section {section.name} to append new data.')
+
+-                padding = bytes(new_section.SizeOfRawData - new_section.Misc_VirtualSize)
++                padding = bytes(s.SizeOfRawData - new_section.Misc_VirtualSize)
+                 pe.__data__ = pe.__data__[:s.PointerToRawData] + data + padding + pe.__data__[pe.sections[i+1].PointerToRawData:]
+-                s.SizeOfRawData = new_section.SizeOfRawData
+                 s.Misc_VirtualSize = new_section.Misc_VirtualSize
+                 break
+         else:
+-- 
+2.45.4
+

.github/workflows/tests-functional.yml

@@ -68,6 +68,14 @@ jobs:
       env:
         HOST_ARCH: ${{ inputs.hostArch }}
 
+    - name: Patch ukify (AZL3)
+      if: inputs.hostDistro == 'azl3'
+      run: |
+        set -eux
+
+        UKIFY_PATH=$(which ukify)
+        sudo patch "$UKIFY_PATH" ./repo/.github/workflows/scripts/ukify-fix-insertion-of-padding-in-merged-sections.patch
+
     - name: Install prerequisites (Ubuntu 24.04)
       if: inputs.hostDistro == 'ubuntu2404'
       run: |
@@ -98,9 +106,11 @@ jobs:
           ./repo/.github/workflows/scripts/download-image.sh "$AZURE_STORAGE" "$AZURE_CONTAINER" "$1" "$2"
         }
 
-        if [[ "$TEST_DISTRO" == "azl" ]]; then
+        if [[ "$TEST_DISTRO" == "azl3" ]]; then
             download "azure-linux/core-efi-vhdx-2.0-$HOST_ARCH" azl-core-efi-2.0
             download "azure-linux/core-efi-vhdx-3.0-$HOST_ARCH" azl-core-efi-3.0
+        elif [[ "$TEST_DISTRO" == "azl4" ]]; then
+            download "azure-linux/core-efi-vhdx-4.0-$HOST_ARCH" azl-core-efi-4.0
         elif [[ "$TEST_DISTRO" == "ubuntu" ]]; then
             download "ubuntu/azure-cloud-vhdx-22.04-$HOST_ARCH" ubuntu-azure-cloud-22.04
             download "ubuntu/azure-cloud-vhdx-24.04-$HOST_ARCH" ubuntu-azure-cloud-24.04
@@ -118,8 +128,10 @@ jobs:
       run: |
         set -eux
         pushd repo/toolkit/tools
-        if [[ "$TEST_DISTRO" == "azl" ]]; then
+        if [[ "$TEST_DISTRO" == "azl3" ]]; then
           ./internal/testutils/testrpms/download-test-utils.sh -d azurelinux -t 3.0 -s true
+        elif [[ "$TEST_DISTRO" == "azl4" ]]; then
+          ./internal/testutils/testrpms/download-test-utils.sh -d azurelinux -t 4.0 -s true
         elif [[ "$TEST_DISTRO" == "ubuntu" ]]; then
           echo "No test utils needed for Ubuntu tests"
         else
@@ -137,12 +149,15 @@ jobs:
 
         AZL2_VHDX=""
         AZL3_VHDX=""
+        AZL4_VHDX=""
         UBUNTU2204_VHDX=""
         UBUNTU2404_VHDX=""
 
-        if [[ "$TEST_DISTRO" == "azl" ]]; then
+        if [[ "$TEST_DISTRO" == "azl3" ]]; then
           AZL2_VHDX="../../../../../azl-core-efi-2.0/image.vhdx"
           AZL3_VHDX="../../../../../azl-core-efi-3.0/image.vhdx"
+        elif [[ "$TEST_DISTRO" == "azl4" ]]; then
+          AZL4_VHDX="../../../../../azl-core-efi-4.0/image.vhdx"
         elif [[ "$TEST_DISTRO" == "ubuntu" ]]; then
           UBUNTU2204_VHDX="../../../../../ubuntu-azure-cloud-22.04/image.vhdx"
           UBUNTU2404_VHDX="../../../../../ubuntu-azure-cloud-24.04/image.vhdx"
@@ -161,6 +176,7 @@ jobs:
           -args \
           --base-image-core-efi-azl2 "$AZL2_VHDX" \
           --base-image-core-efi-azl3 "$AZL3_VHDX" \
+          --base-image-core-efi-azl4 "$AZL4_VHDX" \
           --base-image-azure-cloud-ubuntu2204 "$UBUNTU2204_VHDX" \
           --base-image-azure-cloud-ubuntu2404 "$UBUNTU2404_VHDX" \
           2>&1 \

.github/workflows/tests-vmtests-osmodifier.yml

@@ -123,6 +123,7 @@ jobs:
 
           ./repo/.github/workflows/scripts/download-image.sh "$AZURE_STORAGE" "$AZURE_CONTAINER" "azure-linux/core-efi-vhdx-2.0-$HOST_ARCH" azl-core-efi-2.0
           ./repo/.github/workflows/scripts/download-image.sh "$AZURE_STORAGE" "$AZURE_CONTAINER" "azure-linux/core-efi-vhdx-3.0-$HOST_ARCH" azl-core-efi-3.0
+          ./repo/.github/workflows/scripts/download-image.sh "$AZURE_STORAGE" "$AZURE_CONTAINER" "azure-linux/core-efi-vhdx-4.0-$HOST_ARCH" azl-core-efi-4.0
         env:
           HOST_ARCH: ${{ inputs.hostArch }}
           AZURE_STORAGE: ${{ vars.AZURE_STORAGE }}
@@ -136,9 +137,11 @@ jobs:
 
           AZL2_IMAGE="../../../azl-core-efi-2.0/image.vhdx"
           AZL3_IMAGE="../../../azl-core-efi-3.0/image.vhdx"
+          AZL4_IMAGE="../../../azl-core-efi-4.0/image.vhdx"
 
           echo "azl2_path=$AZL2_IMAGE" >> "$GITHUB_OUTPUT"
           echo "azl3_path=$AZL3_IMAGE" >> "$GITHUB_OUTPUT"
+          echo "azl4_path=$AZL4_IMAGE" >> "$GITHUB_OUTPUT"
 
       - name: Test setup
         run: |
@@ -165,6 +168,8 @@ jobs:
             IMAGE_CUSTOMIZER_CONTAINER_TAG="${IMAGE_CUSTOMIZER_CONTAINER_TAG}" \
             OSMODIFIER_BIN="${OSMODIFIER_BIN}" \
             INPUT_IMAGE="${INPUT_IMAGE}" \
+            DISTRO_ID="azurelinux" \
+            VERSION_ID="2.0" \
             SSH_PRIVATE_KEY_FILE=~/.ssh/id_ed25519
 
       - name: Run tests (AZL3)
@@ -180,6 +185,25 @@ jobs:
             IMAGE_CUSTOMIZER_CONTAINER_TAG="${IMAGE_CUSTOMIZER_CONTAINER_TAG}" \
             OSMODIFIER_BIN="${OSMODIFIER_BIN}" \
             INPUT_IMAGE="${INPUT_IMAGE}" \
+            DISTRO_ID="azurelinux" \
+            VERSION_ID="3.0" \
+            SSH_PRIVATE_KEY_FILE=~/.ssh/id_ed25519
+
+      - name: Run tests (AZL4)
+        env:
+          IMAGE_CUSTOMIZER_CONTAINER_TAG: ${{ steps.importContainer.outputs.containerTag }}
+          OSMODIFIER_BIN: ${{ steps.osmodifier_bin.outputs.path }}
+          INPUT_IMAGE: ${{ steps.setup_image.outputs.azl4_path  }}
+        run: |
+          set -eux
+          pushd ./repo/test/vmtests
+
+          sudo make test-osmodifier \
+            IMAGE_CUSTOMIZER_CONTAINER_TAG="${IMAGE_CUSTOMIZER_CONTAINER_TAG}" \
+            OSMODIFIER_BIN="${OSMODIFIER_BIN}" \
+            INPUT_IMAGE="${INPUT_IMAGE}" \
+            DISTRO_ID="azurelinux" \
+            VERSION_ID="4.0" \
             SSH_PRIVATE_KEY_FILE=~/.ssh/id_ed25519
 
       - uses: actions/upload-artifact@v7

.github/workflows/tests-vmtests.yml

@@ -101,6 +101,7 @@ jobs:
 
         ./repo/.github/workflows/scripts/download-image.sh "$AZURE_STORAGE" "$AZURE_CONTAINER" "azure-linux/core-efi-vhdx-2.0-$HOST_ARCH" azl-core-efi-2.0
         ./repo/.github/workflows/scripts/download-image.sh "$AZURE_STORAGE" "$AZURE_CONTAINER" "azure-linux/core-efi-vhdx-3.0-$HOST_ARCH" azl-core-efi-3.0
+        ./repo/.github/workflows/scripts/download-image.sh "$AZURE_STORAGE" "$AZURE_CONTAINER" "azure-linux/core-efi-vhdx-4.0-$HOST_ARCH" azl-core-efi-4.0
 
         if [ "$HOST_ARCH" == "amd64" ]; then
           ./repo/.github/workflows/scripts/download-image.sh "$AZURE_STORAGE" "$AZURE_CONTAINER" "azure-linux/core-legacy-vhd-2.0-$HOST_ARCH" azl-core-legacy-2.0
@@ -170,6 +171,7 @@ jobs:
           IMAGE_CUSTOMIZER_CONTAINER_TAG="$CONTAINER_TAG" \
           CORE_EFI_AZL2="../../../azl-core-efi-2.0/image.vhdx" \
           CORE_EFI_AZL3="../../../azl-core-efi-3.0/image.vhdx" \
+          CORE_EFI_AZL4="../../../azl-core-efi-4.0/image.vhdx" \
           CORE_LEGACY_AZL2="$CORE_LEGACY_AZL2" \
           CORE_LEGACY_AZL3="$CORE_LEGACY_AZL3" \
           RPM_SOURCES_AZL3="$TEST_RPMS_DIR/downloadedrpms/azurelinux/3.0" \

docs/imagecustomizer/README.md

@@ -59,6 +59,7 @@ other Linux distributions as well.
 Image Customizer supports the following input image distributions:
 
 - Azure Linux 3.0
+- Azure Linux 4.0
 - Ubuntu 22.04
 - Ubuntu 24.04