reproduce (this is a W=1 build):
        mkdir -p ~/bin
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git/commit/?id=f587ec0ba862176b8f48ab73e66516647db95107
        git remote add ardb git://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git
        git fetch --no-tags ardb x86-efi-runtime-cleanup
        git checkout f587ec0ba862176b8f48ab73e66516647db95107
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=x86_64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/platform/x86/