Ship initrd.img in MSI using build-time generation via powershell script

[benhillis]

Replace the install-time CreateInitrd/RemoveInitrd custom actions with a build-time step that generates initrd.img using the a powershell script and ships it directly in the MSI.

Changes:

• Add CMake custom command to generate initrd.img via a powershell script
• Add initrd.img as a regular file in the MSI tools component
• Remove CreateInitrd/RemoveInitrd custom actions from WiX, DllMain, and wslinstall.def
• Remove CreateCpioInitrd helper and its tests (no longer needed)
• Update pipeline build targets to build initramfs instead of init

[Copilot]

Pull request overview

This PR shifts initrd.img handling from an MSI installer-time custom action to a build-time generated artifact that is shipped directly in the MSI, removing the associated helper implementation and tests.

Changes:

• Generate initrd.img during the Linux init build via a new initramfs CMake target and include it in MSI packaging.
• Remove installer custom actions/exports (CreateInitrd/RemoveInitrd) and the Windows-side CreateCpioInitrd helper.
• Remove test coverage that previously validated initrd creation and lifecycle behavior.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/linux/init/CMakeLists.txt	Adds initramfs target to generate initrd.img via tar.exe --format=newc.
msipackage/CMakeLists.txt	Adds initrd.img to MSI inputs and makes msipackage depend on initramfs.
msipackage/package.wix.in	Ships initrd.img as a file in the tools component; removes related custom actions.
src/windows/wslinstall/DllMain.cpp	Removes MSI custom action implementations for initrd create/remove.
src/windows/wslinstall/wslinstall.def	Removes exported symbols for initrd create/remove actions.
src/windows/common/filesystem.hpp	Removes CreateCpioInitrd declaration.
src/windows/common/filesystem.cpp	Removes CreateCpioInitrd implementation.
test/windows/SimpleTests.cpp	Removes unit test for CreateCpioInitrd.
test/windows/InstallerTests.cpp	Removes installer lifecycle test for initrd.img.
.pipelines/build-stage.yml	Updates pipeline target list to build initramfs instead of init.

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[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

test/windows/InstallerTests.cpp:499

• The PR removes the InitrdImgLifecycle installer test, but the change also makes initrd.img a required packaged artifact (built during initramfs and shipped in the MSI). With this test gone, there doesn’t appear to be any remaining validation that tools\\initrd.img is actually installed (and removed) as expected. Consider adding a lightweight check (e.g., existence + non-empty) as part of the install validation to keep coverage for this critical boot dependency.

    TEST_METHOD(UpgradeInstallsTheMsiPackage)
    {
        // Remove the MSIX package
        UninstallMsix();
        VERIFY_IS_FALSE(IsMsixInstalled());

        // Validate that upgrading the MSI installs the MSIX again
        InstallMsi();
        VERIFY_IS_TRUE(IsMsiPackageInstalled());
        VERIFY_IS_TRUE(IsMsixInstalled());
        VERIFY_IS_FALSE(IsMsixInstallerInstalled());
        ValidatePackageInstalledProperly();

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[Copilot]

Pull request overview

Copilot reviewed 11 out of 11 changed files in this pull request and generated 4 comments.

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[Copilot]

Pull request overview

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

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[Copilot]

Pull request overview

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

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[OneBlue]

Is this needed ? The script would exit either way right ?

[benhillis]

You are right, probably not needed, but also not harmful