tree: https://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux.git queue-next head: 63a5ba90039edf87e997048156a17ef57c76436c commit: 63a5ba90039edf87e997048156a17ef57c76436c [2/2] Merge branch 'testing/rdma-next' into queue-next config: arc-allyesconfig (attached as .config) compiler: arceb-elf-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 # https://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux.git/commit... git remote add mellanox https://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux.git git fetch --no-tags mellanox queue-next git checkout 63a5ba90039edf87e997048156a17ef57c76436c # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arc 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 >>): drivers/net/ethernet/intel/igc/igc_main.c: In function '__igc_xdp_run_prog': 2158 | res = IGC_XDP_TX; | ^~~ drivers/net/ethernet/intel/igc/igc_main.c:2158:3: note: each undeclared identifier is reported only once for each function it appears in drivers/net/ethernet/intel/igc/igc_main.c:2175:1: error: control reaches end of non-void function [-Werror=return-type] 2175 | } | ^ cc1: some warnings being treated as errors vim +/res +2158 drivers/net/ethernet/intel/igc/igc_main.c 73f1071c1d2952 Andre Guedes 2021-03-09 2144 73a6e372126152 Andre Guedes 2021-04-22 2145 /* This function assumes rcu_read_lock() is held by the caller. */ 73a6e372126152 Andre Guedes 2021-04-22 2146 static int __igc_xdp_run_prog(struct igc_adapter *adapter, 73a6e372126152 Andre Guedes 2021-04-22 2147 struct bpf_prog *prog, 26575105d6ed8e Andre Guedes 2021-03-09 2148 struct xdp_buff *xdp) 26575105d6ed8e Andre Guedes 2021-03-09 2149 { 73a6e372126152 Andre Guedes 2021-04-22 2150 u32 act = bpf_prog_run_xdp(prog, xdp); 26575105d6ed8e Andre Guedes 2021-03-09 2151 26575105d6ed8e Andre Guedes 2021-03-09 2152 switch (act) { 26575105d6ed8e Andre Guedes 2021-03-09 2153 case XDP_PASS: 73a6e372126152 Andre Guedes 2021-04-22 2154 return IGC_XDP_PASS; 73f1071c1d2952 Andre Guedes 2021-03-09 2155 case XDP_TX: 73f1071c1d2952 Andre Guedes 2021-03-09 2156 if (igc_xdp_xmit_back(adapter, xdp) < 0) 45ce08594ec3a9 Magnus Karlsson 2021-05-10 2157 goto out_failure; 73f1071c1d2952 Andre Guedes 2021-03-09 @2158 res = IGC_XDP_TX; 73f1071c1d2952 Andre Guedes 2021-03-09 2159 break; 4ff3203610928c Andre Guedes 2021-03-09 2160 case XDP_REDIRECT: 4ff3203610928c Andre Guedes 2021-03-09 2161 if (xdp_do_redirect(adapter->netdev, xdp, prog) < 0) 45ce08594ec3a9 Magnus Karlsson 2021-05-10 2162 goto out_failure; 4ff3203610928c Andre Guedes 2021-03-09 2163 res = IGC_XDP_REDIRECT; 4ff3203610928c Andre Guedes 2021-03-09 2164 break; 26575105d6ed8e Andre Guedes 2021-03-09 2165 default: 26575105d6ed8e Andre Guedes 2021-03-09 2166 bpf_warn_invalid_xdp_action(act); 26575105d6ed8e Andre Guedes 2021-03-09 2167 fallthrough; 26575105d6ed8e Andre Guedes 2021-03-09 2168 case XDP_ABORTED: 45ce08594ec3a9 Magnus Karlsson 2021-05-10 2169 out_failure: 26575105d6ed8e Andre Guedes 2021-03-09 2170 trace_xdp_exception(adapter->netdev, prog, act); 26575105d6ed8e Andre Guedes 2021-03-09 2171 fallthrough; 26575105d6ed8e Andre Guedes 2021-03-09 2172 case XDP_DROP: 73a6e372126152 Andre Guedes 2021-04-22 2173 return IGC_XDP_CONSUMED; 73a6e372126152 Andre Guedes 2021-04-22 2174 } 26575105d6ed8e Andre Guedes 2021-03-09 2175 } 26575105d6ed8e Andre Guedes 2021-03-09 2176 :::::: The code at line 2158 was first introduced by commit :::::: 73f1071c1d2952b8c93cd6cd99744768c59ec840 igc: Add support for XDP_TX action :::::: TO: Andre Guedes <andre.guedes(a)intel.com&gt; :::::: CC: Tony Nguyen <anthony.l.nguyen(a)intel.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org