reproduce (this is a W=1 build):
        git remote add openeuler https://gitee.com/openeuler/kernel.git
        git fetch --no-tags openeuler OLK-6.6
        git checkout 468b0cd7b1e1c131b3ee7d2ea8b96521d3faad8b

        # 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 drivers/net/ethernet/nebula-matrix/nbl/