Hi Stanislav,

I love your patch! Yet something to improve:

[auto build test ERROR on bpf-next/master]

url:    https://github.com/intel-lab-lkp/linux/commits/Stanislav-Fomichev/xdp-hints-via-kfuncs/20221130-092141
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
patch link:    https://lore.kernel.org/r/20221129193452.3448944-3-sdf%40google.com
patch subject: [PATCH bpf-next v3 02/11] bpf: XDP metadata RX kfuncs
config: ia64-buildonly-randconfig-r004-20221128
compiler: ia64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/29a0f81ee3719e12a542b11745f60c31066330e5
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Stanislav-Fomichev/xdp-hints-via-kfuncs/20221130-092141
        git checkout 29a0f81ee3719e12a542b11745f60c31066330e5
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=ia64 SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   ia64-linux-ld: kernel/bpf/syscall.o: in function `bpf_prog_load':
   kernel/bpf/syscall.c:2589: undefined reference to `dev_get_by_index'
   ia64-linux-ld: kernel/bpf/verifier.o: in function `resolve_xdp_kfunc_call':
   kernel/bpf/verifier.c:15291: undefined reference to `xdp_metadata_kfunc_id'
>> ia64-linux-ld: kernel/bpf/verifier.c:15293: undefined reference to `xdp_metadata_kfunc_id'
   ia64-linux-ld: kernel/bpf/verifier.c:15295: undefined reference to `xdp_metadata_kfunc_id'
   ia64-linux-ld: kernel/bpf/verifier.c:15297: undefined reference to `xdp_metadata_kfunc_id'

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp