reproduce (this is a W=1 build):
        # https://github.com/dvyukov/linux/commit/a2e8f001038652815e629351cab41bb9ae304fae
        git remote add dvyukov https://github.com/dvyukov/linux
        git fetch --no-tags dvyukov dvyukov-random-sched
        git checkout a2e8f001038652815e629351cab41bb9ae304fae
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=um olddefconfig
        make W=1 O=build_dir ARCH=um SHELL=/bin/bash kernel/