Hi Xin, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on net/master] url: https://github.com/0day-ci/linux/commits/Xin-Long/sctp-do-not-update-transport-pathmtu-if-SPP_PMTUD_ENABLE-is-not-set/20210722-001121 base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git e9a72f874d5b95cef0765bafc56005a50f72c5fe config: arc-allyesconfig (attached as .config) compiler: arceb-elf-gcc (GCC) 10.3.0 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://github.com/0day-ci/linux/commit/e6927d4d69af5f40d7884a7ccc70737bf3da2771 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Xin-Long/sctp-do-not-update-transport-pathmtu-if-SPP_PMTUD_ENABLE-is-not-set/20210722-001121 git checkout e6927d4d69af5f40d7884a7ccc70737bf3da2771 # save the attached .config to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross O=build_dir ARCH=arc SHELL=/bin/bash net/sctp/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): net/sctp/output.c:112:2: error: expected identifier or '(' before 'if' 112 | if (asoc->pmtu_pending) { | ^~ net/sctp/output.c:121:2: error: expected identifier or '(' before 'if' 121 | if (ecn_capable) { | ^~ net/sctp/output.c:128:2: error: expected identifier or '(' before 'if' 128 | if (!tp->dst) | ^~ >> net/sctp/output.c:132:2: warning: data definition has no type or storage class 132 | rcu_read_lock(); | ^~~~~~~~~~~~~ net/sctp/output.c:132:2: error: type defaults to 'int' in declaration of 'rcu_read_lock' [-Werror=implicit-int] net/sctp/output.c:132:2: error: function declaration isn't a prototype [-Werror=strict-prototypes] net/sctp/output.c:132:2: error: conflicting types for 'rcu_read_lock' In file included from include/linux/rbtree.h:22, from include/linux/mm_types.h:10, from include/linux/mmzone.h:21, from include/linux/gfp.h:6, from include/linux/mm.h:10, from include/linux/bvec.h:14, from include/linux/skbuff.h:17, from include/linux/ip.h:16, from net/sctp/output.c:28: include/linux/rcupdate.h:683:29: note: previous definition of 'rcu_read_lock' was here 683 | static __always_inline void rcu_read_lock(void) | ^~~~~~~~~~~~~ net/sctp/output.c:133:2: error: expected identifier or '(' before 'if' 133 | if (__sk_dst_get(sk) != tp->dst) { | ^~ net/sctp/output.c:137:8: error: expected '=', ',', ';', 'asm' or '__attribute__' before '->' token 137 | packet->max_size = sk_can_gso(sk) ? tp->dst->dev->gso_max_size | ^~ net/sctp/output.c:139:2: warning: data definition has no type or storage class 139 | rcu_read_unlock(); | ^~~~~~~~~~~~~~~ net/sctp/output.c:139:2: error: type defaults to 'int' in declaration of 'rcu_read_unlock' [-Werror=implicit-int] net/sctp/output.c:139:2: error: function declaration isn't a prototype [-Werror=strict-prototypes] net/sctp/output.c:139:2: error: conflicting types for 'rcu_read_unlock' In file included from include/linux/rbtree.h:22, from include/linux/mm_types.h:10, from include/linux/mmzone.h:21, from include/linux/gfp.h:6, from include/linux/mm.h:10, from include/linux/bvec.h:14, from include/linux/skbuff.h:17, from include/linux/ip.h:16, from net/sctp/output.c:28: include/linux/rcupdate.h:714:20: note: previous definition of 'rcu_read_unlock' was here 714 | static inline void rcu_read_unlock(void) | ^~~~~~~~~~~~~~~ net/sctp/output.c:140:1: error: expected identifier or '(' before '}' token 140 | } | ^ cc1: some warnings being treated as errors vim +132 net/sctp/output.c be2971438dec2e Wei Yongjun 2009-09-04 69 ^1da177e4c3f41 Linus Torvalds 2005-04-16 70 /* Config a packet. ^1da177e4c3f41 Linus Torvalds 2005-04-16 71 * This appears to be a followup set of initializations. ^1da177e4c3f41 Linus Torvalds 2005-04-16 72 */ 66b91d2cd0344c Marcelo Ricardo Leitner 2016-12-28 73 void sctp_packet_config(struct sctp_packet *packet, __u32 vtag, 66b91d2cd0344c Marcelo Ricardo Leitner 2016-12-28 74 int ecn_capable) ^1da177e4c3f41 Linus Torvalds 2005-04-16 75 { 90017accff61ae Marcelo Ricardo Leitner 2016-06-02 76 struct sctp_transport *tp = packet->transport; 90017accff61ae Marcelo Ricardo Leitner 2016-06-02 77 struct sctp_association *asoc = tp->asoc; feddd6c1af30ab Marcelo Ricardo Leitner 2018-04-26 78 struct sctp_sock *sp = NULL; df2729c3238ed8 Xin Long 2017-04-01 79 struct sock *sk; ^1da177e4c3f41 Linus Torvalds 2005-04-16 80 bb33381d0c97cd Daniel Borkmann 2013-06-28 81 pr_debug("%s: packet:%p vtag:0x%x\n", __func__, packet, vtag); ^1da177e4c3f41 Linus Torvalds 2005-04-16 82 packet->vtag = vtag; ^1da177e4c3f41 Linus Torvalds 2005-04-16 83 df2729c3238ed8 Xin Long 2017-04-01 84 /* do the following jobs only once for a flush schedule */ df2729c3238ed8 Xin Long 2017-04-01 85 if (!sctp_packet_empty(packet)) df2729c3238ed8 Xin Long 2017-04-01 86 return; 90017accff61ae Marcelo Ricardo Leitner 2016-06-02 87 b7e10c25b839c0 Richard Haines 2018-02-24 88 /* set packet max_size with pathmtu, then calculate overhead */ 90017accff61ae Marcelo Ricardo Leitner 2016-06-02 89 packet->max_size = tp->pathmtu; feddd6c1af30ab Marcelo Ricardo Leitner 2018-04-26 90 b7e10c25b839c0 Richard Haines 2018-02-24 91 if (asoc) { feddd6c1af30ab Marcelo Ricardo Leitner 2018-04-26 92 sk = asoc->base.sk; feddd6c1af30ab Marcelo Ricardo Leitner 2018-04-26 93 sp = sctp_sk(sk); feddd6c1af30ab Marcelo Ricardo Leitner 2018-04-26 94 } feddd6c1af30ab Marcelo Ricardo Leitner 2018-04-26 95 packet->overhead = sctp_mtu_payload(sp, 0, 0); feddd6c1af30ab Marcelo Ricardo Leitner 2018-04-26 96 packet->size = packet->overhead; b7e10c25b839c0 Richard Haines 2018-02-24 97 feddd6c1af30ab Marcelo Ricardo Leitner 2018-04-26 98 if (!asoc) df2729c3238ed8 Xin Long 2017-04-01 99 return; 90017accff61ae Marcelo Ricardo Leitner 2016-06-02 100 df2729c3238ed8 Xin Long 2017-04-01 101 /* update dst or transport pathmtu if in need */ df2729c3238ed8 Xin Long 2017-04-01 102 if (!sctp_transport_dst_check(tp)) { feddd6c1af30ab Marcelo Ricardo Leitner 2018-04-26 103 sctp_transport_route(tp, NULL, sp); df2729c3238ed8 Xin Long 2017-04-01 104 if (asoc->param_flags & SPP_PMTUD_ENABLE) 3ebfdf082184d0 Xin Long 2017-04-04 105 sctp_assoc_sync_pmtu(asoc); 7307e4fa4d295f Xin Long 2021-06-22 106 } else if (!sctp_transport_pl_enabled(tp) && e6927d4d69af5f Xin Long 2021-07-21 107 asoc->param_flags & SPP_PMTUD_ENABLE) e6927d4d69af5f Xin Long 2021-07-21 108 if (!sctp_transport_pmtu_check(tp)) 69fec325a64383 Xin Long 2018-11-18 109 sctp_assoc_sync_pmtu(asoc); df2729c3238ed8 Xin Long 2017-04-01 110 } ^1da177e4c3f41 Linus Torvalds 2005-04-16 111 d805397c3822d5 Xin Long 2018-10-15 112 if (asoc->pmtu_pending) { d805397c3822d5 Xin Long 2018-10-15 113 if (asoc->param_flags & SPP_PMTUD_ENABLE) d805397c3822d5 Xin Long 2018-10-15 114 sctp_assoc_sync_pmtu(asoc); d805397c3822d5 Xin Long 2018-10-15 115 asoc->pmtu_pending = 0; d805397c3822d5 Xin Long 2018-10-15 116 } d805397c3822d5 Xin Long 2018-10-15 117 ^1da177e4c3f41 Linus Torvalds 2005-04-16 118 /* If there a is a prepend chunk stick it on the list before ^1da177e4c3f41 Linus Torvalds 2005-04-16 119 * any other chunks get appended. ^1da177e4c3f41 Linus Torvalds 2005-04-16 120 */ df2729c3238ed8 Xin Long 2017-04-01 121 if (ecn_capable) { df2729c3238ed8 Xin Long 2017-04-01 122 struct sctp_chunk *chunk = sctp_get_ecne_prepend(asoc); df2729c3238ed8 Xin Long 2017-04-01 123 ^1da177e4c3f41 Linus Torvalds 2005-04-16 124 if (chunk) ^1da177e4c3f41 Linus Torvalds 2005-04-16 125 sctp_packet_append_chunk(packet, chunk); ^1da177e4c3f41 Linus Torvalds 2005-04-16 126 } df2729c3238ed8 Xin Long 2017-04-01 127 df2729c3238ed8 Xin Long 2017-04-01 128 if (!tp->dst) df2729c3238ed8 Xin Long 2017-04-01 129 return; df2729c3238ed8 Xin Long 2017-04-01 130 df2729c3238ed8 Xin Long 2017-04-01 131 /* set packet max_size with gso_max_size if gso is enabled*/ df2729c3238ed8 Xin Long 2017-04-01 @132 rcu_read_lock(); df2729c3238ed8 Xin Long 2017-04-01 133 if (__sk_dst_get(sk) != tp->dst) { df2729c3238ed8 Xin Long 2017-04-01 134 dst_hold(tp->dst); df2729c3238ed8 Xin Long 2017-04-01 135 sk_setup_caps(sk, tp->dst); df2729c3238ed8 Xin Long 2017-04-01 136 } df2729c3238ed8 Xin Long 2017-04-01 137 packet->max_size = sk_can_gso(sk) ? tp->dst->dev->gso_max_size df2729c3238ed8 Xin Long 2017-04-01 138 : asoc->pathmtu; df2729c3238ed8 Xin Long 2017-04-01 139 rcu_read_unlock(); ^1da177e4c3f41 Linus Torvalds 2005-04-16 140 } ^1da177e4c3f41 Linus Torvalds 2005-04-16 141 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org