tree: git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git master head: 05f90bf3d5df40e1a705527520e5fd56b2b6f09e commit: 010b430d5df556d5d232e3751ac691ba9e88c041 [26/31] mptcp: MPTCP_IPV6 should depend on IPV6 instead of selecting it config: sh-allmodconfig (attached as .config) compiler: sh4-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/netdev/net.git/commit/?id... git remote add netdev-net git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git git fetch --no-tags netdev-net master git checkout 010b430d5df556d5d232e3751ac691ba9e88c041 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sh 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 >>): sh4-linux-ld: net/mptcp/protocol.o: in function `mptcp_stream_accept': protocol.c:(.text+0x1d7c): undefined reference to `tcpv6_prot' sh4-linux-ld: net/mptcp/protocol.o: in function `mptcp_v6_destroy': protocol.c:(.text+0x5cb4): undefined reference to `inet6_destroy_sock' sh4-linux-ld: net/mptcp/protocol.o: in function `mptcp_proto_v6_init': sh4-linux-ld: net/mptcp/subflow.o: in function `subflow_v6_init_req': subflow.c:(.text+0x1dcc): undefined reference to `tcp_request_sock_ipv6_ops' sh4-linux-ld: net/mptcp/subflow.o: in function `mptcp_subflow_init': (.init.text+0x140): undefined reference to `tcp_request_sock_ipv6_ops' --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org