reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/bp/bp.git/commit/?id=a05a1e35e67bfe03704633c51ca9b03e16fffd06
        git remote add bp https://git.kernel.org/pub/scm/linux/kernel/git/bp/bp.git
        git fetch --no-tags bp tip-x86-cpu-tlbi
        git checkout a05a1e35e67bfe03704633c51ca9b03e16fffd06
        # 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 arch/x86/