reproduce (this is a W=1 build):
        # https://github.com/gmprice/linux/commit/fcf523ffd2839c474457c3af29555129848d8eb3
        git remote add gmprice https://github.com/gmprice/linux
        git fetch --no-tags gmprice mempolicy2_mbind2
        git checkout fcf523ffd2839c474457c3af29555129848d8eb3
        # 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 mm/