reproduce (this is a W=1 build):
        git remote add net-next https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
        git fetch net-next main
        git checkout net-next/main
        b4 shazam https://lore.kernel.org/r/1708412505-34470-20-git-send-email-alibuda@linux.alibaba.com
        # 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 net/smc/