reproduce (this is a W=1 build):
        git checkout e538109ac71d801d26776af5f3c54f548296c29c
        b4 shazam https://lore.kernel.org/r/20251202-configfs_netcon-v1-2-b4738ead8ee8@debian.org

        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=i386 olddefconfig
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash