Hi Paolo, FYI, the error/warning still remains. tree: https://github.com/multipath-tcp/mptcp_net-next.git export head: 502db67b77b326a9be8f3bb3515a09b83a8a1fd4 commit: 91e9b96e7c81bb06efcbd05a454d61c735f8c519 [776/783] mptcp: open code mptcp variant for lock_sock config: nds32-randconfig-r032-20201119 (attached as .config) compiler: nds32le-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://github.com/multipath-tcp/mptcp_net-next/commit/91e9b96e7c81bb06ef... git remote add mptcp https://github.com/multipath-tcp/mptcp_net-next.git git fetch --no-tags mptcp export git checkout 91e9b96e7c81bb06efcbd05a454d61c735f8c519 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=nds32 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): 2489 | void __lock_sock(struct sock *sk) | ^~~~~~~~~~~ vim +/__lock_sock +2489 net/core/sock.c 2488 2490 __releases(&sk->sk_lock.slock) 2491 __acquires(&sk->sk_lock.slock) 2492 { 2493 DEFINE_WAIT(wait); 2494 2495 for (;;) { 2496 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 2497 TASK_UNINTERRUPTIBLE); 2498 spin_unlock_bh(&sk->sk_lock.slock); 2499 schedule(); 2500 spin_lock_bh(&sk->sk_lock.slock); 2501 if (!sock_owned_by_user(sk)) 2502 break; 2503 } 2504 finish_wait(&sk->sk_lock.wq, &wait); 2505 } 2506 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org