reproduce (this is a W=1 build):
        # https://github.com/norov/linux/commit/bba742e7f4aab4b879cc1620c1b57be76607bff8
        git remote add norov https://github.com/norov/linux
        git fetch --no-tags norov compat_get_cpumask
        git checkout bba742e7f4aab4b879cc1620c1b57be76607bff8
        # 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