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/451ae2a5c2ddb3c127cfddaf4a6579d6e85791f3.1717206060.git.yan@cloudflare.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/core/