reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/alobakin/linux/commit/22a26f973e9f391d46318e0768a9ca9a546e25ac
        git remote add alobakin https://github.com/alobakin/linux
        git fetch --no-tags alobakin libeth
        git checkout 22a26f973e9f391d46318e0768a9ca9a546e25ac
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-7.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-7.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash drivers/net/ethernet/intel/idpf/