tree: https://git.kernel.org/pub/scm/linux/kernel/git/toke/linux.git xdp-queueing-01 head: 6b5756c44933d2b55e5e59e1196ef95894203cf7 commit: 6b5756c44933d2b55e5e59e1196ef95894203cf7 [3/3] xdp: add dequeue program type for getting packets from a PIFO config: um-x86_64_defconfig (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/toke/linux.git/commit/?id... git remote add toke https://git.kernel.org/pub/scm/linux/kernel/git/toke/linux.git git fetch --no-tags toke xdp-queueing-01 git checkout 6b5756c44933d2b55e5e59e1196ef95894203cf7 # save the attached .config to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=um SUBARCH=x86_64 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): net/core/filter.c: In function 'xdp_do_redirect': net/core/filter.c:3984:10: error: implicit declaration of function 'pifo_map_enqueue'; did you mean 'cpu_map_enqueue'? [-Werror=implicit-function-declaration] 3984 | err = pifo_map_enqueue(map, xdp, ri->tgt_index); | ^~~~~~~~~~~~~~~~ | cpu_map_enqueue net/core/filter.c: At top level: 9932 | .test_run = bpf_prog_test_run_dequeue, | ^~~~~~~~~~~~~~~~~~~~~~~~~ | bpf_prog_test_run_syscall cc1: some warnings being treated as errors vim +9932 net/core/filter.c 9930 9931 const struct bpf_prog_ops dequeue_prog_ops = { 9933 }; 9934 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org