reproduce (this is a W=1 build):
        # https://github.com/kkdwivedi/linux/commit/7a9d3d30a1aaf04d812c1ccb01d50db1cb62083b
        git remote add kkdwivedi https://github.com/kkdwivedi/linux
        git fetch --no-tags kkdwivedi bpf-napi
        git checkout 7a9d3d30a1aaf04d812c1ccb01d50db1cb62083b

        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests

        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-8.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=xtensa olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-8.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=xtensa SHELL=/bin/bash