tree: https://git.kernel.org/pub/scm/linux/kernel/git/kuba/linux.git tapi head: 328004163c637a4505698baa71e5be0c3ee88d95 commit: d5677ae5c13a4a2304e494bc9252791831145c45 [16/30] taip: add wake up penalties config: arm-randconfig-p001-20200822 (attached as .config) compiler: arm-linux-gnueabi-gcc (GCC) 9.3.0 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 git checkout d5677ae5c13a4a2304e494bc9252791831145c45 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm 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 >>): arm-linux-gnueabi-ld: net/core/dev.o: in function `find_ripe_napi': arm-linux-gnueabi-ld: net/core/dev.c:6905: undefined reference to `__aeabi_ldivmod' # https://git.kernel.org/pub/scm/linux/kernel/git/kuba/linux.git/commit/?id... git remote add kuba-linux https://git.kernel.org/pub/scm/linux/kernel/git/kuba/linux.git git fetch --no-tags kuba-linux tapi git checkout d5677ae5c13a4a2304e494bc9252791831145c45 vim +6893 net/core/dev.c 6850 6851 static struct napi_struct * 6852 find_ripe_napi(struct net_device *dev, bool from_idle, s64 *to) 6853 { 6854 struct napi_struct *napi, *most_ripe = NULL; 6855 u64 oldest_poll = U64_MAX, sum = 0, cnt = 0; 6856 bool has_locals = false; 6857 u64 now; 6858 6859 *to = TAPI_BREAK_PREC_NS; 6860 6861 list_for_each_entry(napi, &dev->napi_list, dev_list) { 6862 u64 biased_time; 6863 6864 /* if TAPI_POLLING is set SCHED is never cleared */ 6865 if (napi->state & (NAPIF_STATE_DISABLE | 6866 NAPIF_STATE_CLAIMED) || 6867 !test_bit(NAPI_STATE_SCHED, &napi->state)) 6868 continue; 6869 6870 cnt++; 6871 sum += napi->last_poll; 6872 6873 biased_time = napi->last_poll; 6874 if (napi->last_poll_thread == current) { 6875 biased_time -= TAPI_LOCAL_BIAS_TIME_NS; 6876 has_locals = true; 6877 } 6878 6879 if (biased_time >= oldest_poll) 6880 continue; 6881 oldest_poll = biased_time; 6882 most_ripe = napi; 6883 } 6884 6885 if (!most_ripe) 6886 return NULL; 6887 6888 now = ktime_get_ns(); 6889 trace_napi_poller_select(most_ripe, now, from_idle); 6890 6891 if (TAPI_POLLING) { 6892 if (!has_locals && TAPI_WA_LATENCY_NS) { 6894 6895 trace_napi_poller_avg_lat(avg_lat); 6896 if (avg_lat < TAPI_WA_LATENCY_NS) 6897 return NULL; 6898 } 6899 6900 *to = oldest_poll 6901 + TAPI_LOCAL_BIAS_TIME_NS 6902 + TAPI_UNREADY_TIME_NS 6903 + from_idle * TAPI_IDLE_PENALTY_NS 6904 - now; 6905 *to /= 1000; 6906 if (*to > 0) 6907 return NULL; 6908 } 6909 6910 if (most_ripe->last_poll_thread == current) 6911 TAPI_CNT_LOCAL++; 6912 else 6913 TAPI_CNT_STEAL++; 6914 6915 return most_ripe; 6916 } 6917 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org