reproduce (this is a W=1 build):
        # https://github.com/rgushchin/linux/commit/7fb104a83d94f08496291125374fdf7c49ea7baa
        git remote add rgushchin https://github.com/rgushchin/linux.git
        git fetch --no-tags rgushchin page_counters.1
        git checkout 7fb104a83d94f08496291125374fdf7c49ea7baa
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=um SUBARCH=i386 olddefconfig
        make W=1 O=build_dir ARCH=um SUBARCH=i386 SHELL=/bin/bash kernel/ mm/