reproduce (this is a W=1 build):
        # https://github.com/yiliu1765/iommufd/commit/9ff1a7ee87c0501007931ac8e72d99a91a629421
        git remote add yiliu1765-iommufd https://github.com/yiliu1765/iommufd.git
        git fetch --no-tags yiliu1765-iommufd wip/iommufd_pasid-20240912
        git checkout 9ff1a7ee87c0501007931ac8e72d99a91a629421
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=i386 olddefconfig
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash