Hi Geliang, Thank you for the patch! Yet something to improve: [auto build test ERROR on linus/master] [also build test ERROR on v5.15-rc6 next-20211021] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Geliang-Tang/Squash-to-mptcp-inf... base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 2f111a6fd5b5297b4e92f53798ca086f7c7d33a4 config: hexagon-randconfig-r045-20211021 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 3cea2505fd8d99a9ba0cb625aecfe28a47c4e3f8) 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://github.com/0day-ci/linux/commit/ca85326898507008f999c544140bfcecb... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Geliang-Tang/Squash-to-mptcp-infinite-mapping-receiving/20211021-140855 git checkout ca85326898507008f999c544140bfcecb30316b3 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=hexagon 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 >>): if (mptcp_check_fallback(ssk) && !mptcp_check_infinite_map(skb)) ^ 1 error generated. -- net/mptcp/options.c:566:21: warning: parameter 'remaining' set but not used [-Wunused-but-set-parameter] unsigned int remaining, ^ mpext->infinite_map = 1; ~~~~~ ^ 1 warning and 1 error generated. vim +/mptcp_check_infinite_map +941 net/mptcp/subflow.c 926 927 static enum mapping_status get_mapping_status(struct sock *ssk, 928 struct mptcp_sock *msk) 929 { 930 struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); 931 bool csum_reqd = READ_ONCE(msk->csum_enabled); 932 struct mptcp_ext *mpext; 933 struct sk_buff *skb; 934 u16 data_len; 935 u64 map_seq; 936 937 skb = skb_peek(&ssk->sk_receive_queue); 938 if (!skb) 939 return MAPPING_EMPTY; 940 942 return MAPPING_DUMMY; 943 944 mpext = mptcp_get_ext(skb); 945 if (!mpext || !mpext->use_map) { 946 if (!subflow->map_valid && !skb->len) { 947 /* the TCP stack deliver 0 len FIN pkt to the receive 948 * queue, that is the only 0len pkts ever expected here, 949 * and we can admit no mapping only for 0 len pkts 950 */ 951 if (!(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) 952 WARN_ONCE(1, "0len seq %d:%d flags %x", 953 TCP_SKB_CB(skb)->seq, 954 TCP_SKB_CB(skb)->end_seq, 955 TCP_SKB_CB(skb)->tcp_flags); 956 sk_eat_skb(ssk, skb); 957 return MAPPING_EMPTY; 958 } 959 960 if (!subflow->map_valid) 961 return MAPPING_INVALID; 962 963 goto validate_seq; 964 } 965 966 trace_get_mapping_status(mpext); 967 968 data_len = mpext->data_len; 969 if (data_len == 0) { 970 MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_INFINITEMAPRX); 971 return MAPPING_INVALID; 972 } 973 974 if (mpext->data_fin == 1) { 975 if (data_len == 1) { 976 bool updated = mptcp_update_rcv_data_fin(msk, mpext->data_seq, 977 mpext->dsn64); 978 pr_debug("DATA_FIN with no payload seq=%llu", mpext->data_seq); 979 if (subflow->map_valid) { 980 /* A DATA_FIN might arrive in a DSS 981 * option before the previous mapping 982 * has been fully consumed. Continue 983 * handling the existing mapping. 984 */ 985 skb_ext_del(skb, SKB_EXT_MPTCP); 986 return MAPPING_OK; 987 } else { 988 if (updated && schedule_work(&msk->work)) 989 sock_hold((struct sock *)msk); 990 991 return MAPPING_DATA_FIN; 992 } 993 } else { 994 u64 data_fin_seq = mpext->data_seq + data_len - 1; 995 996 /* If mpext->data_seq is a 32-bit value, data_fin_seq 997 * must also be limited to 32 bits. 998 */ 999 if (!mpext->dsn64) 1000 data_fin_seq &= GENMASK_ULL(31, 0); 1001 1002 mptcp_update_rcv_data_fin(msk, data_fin_seq, mpext->dsn64); 1003 pr_debug("DATA_FIN with mapping seq=%llu dsn64=%d", 1004 data_fin_seq, mpext->dsn64); 1005 } 1006 1007 /* Adjust for DATA_FIN using 1 byte of sequence space */ 1008 data_len--; 1009 } 1010 1011 map_seq = mptcp_expand_seq(READ_ONCE(msk->ack_seq), mpext->data_seq, mpext->dsn64); 1012 WRITE_ONCE(mptcp_sk(subflow->conn)->use_64bit_ack, !!mpext->dsn64); 1013 1014 if (subflow->map_valid) { 1015 /* Allow replacing only with an identical map */ 1016 if (subflow->map_seq == map_seq && 1017 subflow->map_subflow_seq == mpext->subflow_seq && 1018 subflow->map_data_len == data_len && 1019 subflow->map_csum_reqd == mpext->csum_reqd) { 1020 skb_ext_del(skb, SKB_EXT_MPTCP); 1021 goto validate_csum; 1022 } 1023 1024 /* If this skb data are fully covered by the current mapping, 1025 * the new map would need caching, which is not supported 1026 */ 1027 if (skb_is_fully_mapped(ssk, skb)) { 1028 MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DSSNOMATCH); 1029 return MAPPING_INVALID; 1030 } 1031 1032 /* will validate the next map after consuming the current one */ 1033 goto validate_csum; 1034 } 1035 1036 subflow->map_seq = map_seq; 1037 subflow->map_subflow_seq = mpext->subflow_seq; 1038 subflow->map_data_len = data_len; 1039 subflow->map_valid = 1; 1040 subflow->map_data_fin = mpext->data_fin; 1041 subflow->mpc_map = mpext->mpc_map; 1042 subflow->map_csum_reqd = mpext->csum_reqd; 1043 subflow->map_csum_len = 0; 1044 subflow->map_data_csum = csum_unfold(mpext->csum); 1045 1046 /* Cfr RFC 8684 Section 3.3.0 */ 1047 if (unlikely(subflow->map_csum_reqd != csum_reqd)) 1048 return MAPPING_INVALID; 1049 1050 pr_debug("new map seq=%llu subflow_seq=%u data_len=%u csum=%d:%u", 1051 subflow->map_seq, subflow->map_subflow_seq, 1052 subflow->map_data_len, subflow->map_csum_reqd, 1053 subflow->map_data_csum); 1054 1055 validate_seq: 1056 /* we revalidate valid mapping on new skb, because we must ensure 1057 * the current skb is completely covered by the available mapping 1058 */ 1059 if (!validate_mapping(ssk, skb)) { 1060 MPTCP_INC_STATS(sock_net(ssk), MPTCP_MIB_DSSTCPMISMATCH); 1061 return MAPPING_INVALID; 1062 } 1063 1064 skb_ext_del(skb, SKB_EXT_MPTCP); 1065 1066 validate_csum: 1067 return validate_data_csum(ssk, skb, csum_reqd); 1068 } 1069 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org