Hi "Toke, I love your patch! Yet something to improve: [auto build test ERROR on bpf-next/master] url: https://github.com/0day-ci/linux/commits/Toke-H-iland-J-rgensen/xdp-Support-multiple-programs-on-a-single-interface-through-chain-calls/20191003-005238 base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master config: i386-tinyconfig (attached as .config) compiler: gcc-7 (Debian 7.4.0-13) 7.4.0 reproduce: # save the attached .config to linux build tree make ARCH=i386 If you fix the issue, kindly add following tag Reported-by: kbuild test robot All error/warnings (new ones prefixed by >>): In file included from include/net/sock.h:59:0, from include/linux/tcp.h:19, from include/linux/ipv6.h:87, from include/net/ipv6.h:12, from include/linux/sunrpc/clnt.h:28, from include/linux/nfs_fs.h:32, from init/do_mounts.c:23: include/linux/filter.h: In function 'bpf_prog_run_xdp': >> include/linux/filter.h:725:10: error: implicit declaration of function 'bpf_xdp_chain_map_get_prog' [-Werror=implicit-function-declaration] prog = bpf_xdp_chain_map_get_prog(chain_map, prog->aux->id, ret); ^~~~~~~~~~~~~~~~~~~~~~~~~~ >> include/linux/filter.h:725:8: warning: assignment makes pointer from integer without a cast [-Wint-conversion] prog = bpf_xdp_chain_map_get_prog(chain_map, prog->aux->id, ret); ^ cc1: some warnings being treated as errors vim +/bpf_xdp_chain_map_get_prog +725 include/linux/filter.h 695 696 #define BPF_XDP_MAX_CHAIN_CALLS 32 697 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, 698 struct xdp_buff *xdp) 699 { 700 /* Caller needs to hold rcu_read_lock() (!), otherwise program 701 * can be released while still running, or map elements could be 702 * freed early while still having concurrent users. XDP fastpath 703 * already takes rcu_read_lock() when fetching the program, so 704 * it's not necessary here anymore. 705 */ 706 707 int i = BPF_XDP_MAX_CHAIN_CALLS; 708 struct bpf_map *chain_map; 709 u32 ret; 710 711 chain_map = rcu_dereference(xdp->rxq->dev->xdp_chain_map); 712 if (!chain_map) 713 return BPF_PROG_RUN(prog, xdp); 714 715 do { 716 if (!--i) { 717 ret = XDP_ABORTED; 718 goto out; 719 } 720 721 ret = BPF_PROG_RUN(prog, xdp); 722 if (ret == XDP_ABORTED) 723 goto out; 724 > 725 prog = bpf_xdp_chain_map_get_prog(chain_map, prog->aux->id, ret); 726 } while(prog); 727 728 out: 729 return ret; 730 } 731 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation