Re: [netdev-net-next:main 26/28] ld.lld: error: undefined symbol: efx_tc_netdev_event

[Simon Horman <simon.horman@corigine.com>]

On Sat, Jun 10, 2023 at 09:10:45PM +0800, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git main
> head:   e431e712c83676a8a9cd3988b323e3ef994a8ff3
> commit: 7e5e7d800011adf4aeda615f8a1bc31c0c1e2bb9 [26/28] sfc: neighbour lookup for TC encap action offload
> config: arm-randconfig-r011-20230610 (https://download.01.org/0day-ci/archive/20230610/202306102026.ISK5JfUQ-lkp@intel.com/config)
> compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a)
> reproduce (this is a W=1 build):
>         mkdir -p ~/bin
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # install arm cross compiling tool for clang build
>         # apt-get install binutils-arm-linux-gnueabi
>         # https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=7e5e7d800011adf4aeda615f8a1bc31c0c1e2bb9
>         git remote add netdev-net-next https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git
>         git fetch --no-tags netdev-net-next main
>         git checkout 7e5e7d800011adf4aeda615f8a1bc31c0c1e2bb9
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=arm olddefconfig
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202306102026.ISK5JfUQ-lkp@intel.com/
> 
> All errors (new ones prefixed by >>):
> 
> >> ld.lld: error: undefined symbol: efx_tc_netdev_event
>    >>> referenced by ef100_netdev.c:313 (drivers/net/ethernet/sfc/ef100_netdev.c:313)
>    >>>               drivers/net/ethernet/sfc/ef100_netdev.o:(ef100_netdev_event) in archive vmlinux.a
> --
> >> ld.lld: error: undefined symbol: efx_tc_netevent_event
>    >>> referenced by ef100_netdev.c:329 (drivers/net/ethernet/sfc/ef100_netdev.c:329)
>    >>>               drivers/net/ethernet/sfc/ef100_netdev.o:(ef100_netevent_event) in archive vmlinux.a

A cursory investigation leads me to thinking this occurs
if the CONFIG_SFC is set but CONFIG_SFC_SRIOV is not.