Hi Linus, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: cd557f1c605fc5a2c0eb0b540610f50dc67dd849 commit: 1a3065a26807b4cdd65d3b696ddb18385610f7da [2707/3150] net: bridge: mcast: prepare is-router function for mcast router split config: mips-randconfig-r012-20210514 (attached as .config) compiler: mips-linux-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/next/linux-next.git/commi... git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout 1a3065a26807b4cdd65d3b696ddb18385610f7da # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross W=1 ARCH=mips 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 >>): net/bridge/br_input.c: In function 'br_handle_frame_finish': 135 | br_multicast_is_router(br, skb)) { | ^~~~~~~~~~~~~~~~~~~~~~ In file included from net/bridge/br_input.c:23: net/bridge/br_private.h:1059:20: note: declared here 1059 | static inline bool br_multicast_is_router(struct net_bridge *br) | ^~~~~~~~~~~~~~~~~~~~~~ vim +/br_multicast_is_router +135 net/bridge/br_input.c 65 66 /* note: already called with rcu_read_lock */ 67 int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb) 68 { 69 struct net_bridge_port *p = br_port_get_rcu(skb->dev); 70 enum br_pkt_type pkt_type = BR_PKT_UNICAST; 71 struct net_bridge_fdb_entry *dst = NULL; 72 struct net_bridge_mdb_entry *mdst; 73 bool local_rcv, mcast_hit = false; 74 struct net_bridge *br; 75 u16 vid = 0; 76 u8 state; 77 78 if (!p || p->state == BR_STATE_DISABLED) 79 goto drop; 80 81 state = p->state; 82 if (!br_allowed_ingress(p->br, nbp_vlan_group_rcu(p), skb, &vid, 83 &state)) 84 goto out; 85 86 nbp_switchdev_frame_mark(p, skb); 87 88 /* insert into forwarding database after filtering to avoid spoofing */ 89 br = p->br; 90 if (p->flags & BR_LEARNING) 91 br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, 0); 92 93 local_rcv = !!(br->dev->flags & IFF_PROMISC); 94 if (is_multicast_ether_addr(eth_hdr(skb)->h_dest)) { 95 /* by definition the broadcast is also a multicast address */ 96 if (is_broadcast_ether_addr(eth_hdr(skb)->h_dest)) { 97 pkt_type = BR_PKT_BROADCAST; 98 local_rcv = true; 99 } else { 100 pkt_type = BR_PKT_MULTICAST; 101 if (br_multicast_rcv(br, p, skb, vid)) 102 goto drop; 103 } 104 } 105 106 if (state == BR_STATE_LEARNING) 107 goto drop; 108 109 BR_INPUT_SKB_CB(skb)->brdev = br->dev; 110 BR_INPUT_SKB_CB(skb)->src_port_isolated = !!(p->flags & BR_ISOLATED); 111 112 if (IS_ENABLED(CONFIG_INET) && 113 (skb->protocol == htons(ETH_P_ARP) || 114 skb->protocol == htons(ETH_P_RARP))) { 115 br_do_proxy_suppress_arp(skb, br, vid, p); 116 } else if (IS_ENABLED(CONFIG_IPV6) && 117 skb->protocol == htons(ETH_P_IPV6) && 118 br_opt_get(br, BROPT_NEIGH_SUPPRESS_ENABLED) && 119 pskb_may_pull(skb, sizeof(struct ipv6hdr) + 120 sizeof(struct nd_msg)) && 121 ipv6_hdr(skb)->nexthdr == IPPROTO_ICMPV6) { 122 struct nd_msg *msg, _msg; 123 124 msg = br_is_nd_neigh_msg(skb, &_msg); 125 if (msg) 126 br_do_suppress_nd(skb, br, vid, p, msg); 127 } 128 129 switch (pkt_type) { 130 case BR_PKT_MULTICAST: 131 mdst = br_mdb_get(br, skb, vid); 132 if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) && 133 br_multicast_querier_exists(br, eth_hdr(skb), mdst)) { 134 if ((mdst && mdst->host_joined) || 136 local_rcv = true; 137 br->dev->stats.multicast++; 138 } 139 mcast_hit = true; 140 } else { 141 local_rcv = true; 142 br->dev->stats.multicast++; 143 } 144 break; 145 case BR_PKT_UNICAST: 146 dst = br_fdb_find_rcu(br, eth_hdr(skb)->h_dest, vid); 147 break; 148 default: 149 break; 150 } 151 152 if (dst) { 153 unsigned long now = jiffies; 154 155 if (test_bit(BR_FDB_LOCAL, &dst->flags)) 156 return br_pass_frame_up(skb); 157 158 if (now != dst->used) 159 dst->used = now; 160 br_forward(dst->dst, skb, local_rcv, false); 161 } else { 162 if (!mcast_hit) 163 br_flood(br, skb, pkt_type, local_rcv, false); 164 else 165 br_multicast_flood(mdst, skb, local_rcv, false); 166 } 167 168 if (local_rcv) 169 return br_pass_frame_up(skb); 170 171 out: 172 return 0; 173 drop: 174 kfree_skb(skb); 175 goto out; 176 } 177 EXPORT_SYMBOL_GPL(br_handle_frame_finish); 178 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org