reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git/commit/?id=0fd158c1ea0cc70434a52b4b812cbec4579b9f66
        git remote add cxl https://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git
        git fetch --no-tags cxl next
        git checkout 0fd158c1ea0cc70434a52b4b812cbec4579b9f66
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 olddefconfig
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/cxl/