tree: https://github.com/multipath-tcp/mptcp_net-next.git export head: 630f1178e1faac796df4befc319c19c3fede6b7b commit: 0da79c831507209d7bb2ed905aa738545d0bbe7c [489/515] bpf: add 'bpf_mptcp_sock' structure and helper config: arm64-randconfig-r032-20201113 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 9a85643cd357e412cff69067bb5c4840e228c2ab) 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 # install arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://github.com/multipath-tcp/mptcp_net-next/commit/0da79c831507209d7b... git remote add mptcp https://github.com/multipath-tcp/mptcp_net-next.git git fetch --no-tags mptcp export git checkout 0da79c831507209d7bb2ed905aa738545d0bbe7c # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 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 >>): In file included from kernel/bpf/verifier.c:12: In file included from include/linux/bpf_verifier.h:8: In file included from include/linux/filter.h:13: include/linux/skbuff.h:4622:26: error: implicit declaration of function 'skb_ext_add' [-Werror,-Wimplicit-function-declaration] u64 *kcov_handle_ptr = skb_ext_add(skb, SKB_EXT_KCOV_HANDLE); ^ include/linux/skbuff.h:4622:43: error: use of undeclared identifier 'SKB_EXT_KCOV_HANDLE' u64 *kcov_handle_ptr = skb_ext_add(skb, SKB_EXT_KCOV_HANDLE); ^ include/linux/skbuff.h:4631:21: error: implicit declaration of function 'skb_ext_find' [-Werror,-Wimplicit-function-declaration] u64 *kcov_handle = skb_ext_find(skb, SKB_EXT_KCOV_HANDLE); ^ include/linux/skbuff.h:4631:39: error: use of undeclared identifier 'SKB_EXT_KCOV_HANDLE' u64 *kcov_handle = skb_ext_find(skb, SKB_EXT_KCOV_HANDLE); ^ valid = bpf_mptcp_sock_is_valid_access(off, size, t, &info); ^ kernel/bpf/verifier.c:2844:11: note: did you mean 'bpf_tcp_sock_is_valid_access'? include/linux/bpf.h:1944:20: note: 'bpf_tcp_sock_is_valid_access' declared here static inline bool bpf_tcp_sock_is_valid_access(int off, int size, ^ convert_ctx_access = bpf_mptcp_sock_convert_ctx_access; ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ bpf_tcp_sock_convert_ctx_access include/linux/bpf.h:1951:19: note: 'bpf_tcp_sock_convert_ctx_access' declared here static inline u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type, ^ 6 errors generated. vim +/bpf_mptcp_sock_is_valid_access +2844 kernel/bpf/verifier.c 2817 2818 static int check_sock_access(struct bpf_verifier_env *env, int insn_idx, 2819 u32 regno, int off, int size, 2820 enum bpf_access_type t) 2821 { 2822 struct bpf_reg_state *regs = cur_regs(env); 2823 struct bpf_reg_state *reg = &regs[regno]; 2824 struct bpf_insn_access_aux info = {}; 2825 bool valid; 2826 2827 if (reg->smin_value < 0) { 2828 verbose(env, "R%d min value is negative, either use unsigned index or do a if (index >=0) check.\n", 2829 regno); 2830 return -EACCES; 2831 } 2832 2833 switch (reg->type) { 2834 case PTR_TO_SOCK_COMMON: 2835 valid = bpf_sock_common_is_valid_access(off, size, t, &info); 2836 break; 2837 case PTR_TO_SOCKET: 2838 valid = bpf_sock_is_valid_access(off, size, t, &info); 2839 break; 2840 case PTR_TO_TCP_SOCK: 2841 valid = bpf_tcp_sock_is_valid_access(off, size, t, &info); 2842 break; 2843 case PTR_TO_MPTCP_SOCK: 2845 break; 2846 case PTR_TO_XDP_SOCK: 2847 valid = bpf_xdp_sock_is_valid_access(off, size, t, &info); 2848 break; 2849 default: 2850 valid = false; 2851 } 2852 2853 2854 if (valid) { 2855 env->insn_aux_data[insn_idx].ctx_field_size = 2856 info.ctx_field_size; 2857 return 0; 2858 } 2859 2860 verbose(env, "R%d invalid %s access off=%d size=%d\n", 2861 regno, reg_type_str[reg->type], off, size); 2862 2863 return -EACCES; 2864 } 2865 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org