Hi Jakub, I love your patch! Perhaps something to improve: [auto build test WARNING on bpf-next/master] [also build test WARNING on net-next/master next-20200526] [cannot apply to bpf/master net/master linus/master v5.7-rc7] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Jakub-Sitnicki/Link-based-progra... base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master config: arm-randconfig-r035-20200527 (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 3393cc4cebf9969db94dc424b7a2b6195589c33b) 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 # install arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>, old ones prefixed by <<): if (net) ^~~ kernel/bpf/net_namespace.c:134:26: note: uninitialized use occurs here info->netns.netns_ino = inum; ^~~~ kernel/bpf/net_namespace.c:130:2: note: remove the 'if' if its condition is always true if (net) ^~~~~~~~ kernel/bpf/net_namespace.c:123:19: note: initialize the variable 'inum' to silence this warning unsigned int inum; ^ = 0 1 warning generated. vim +130 kernel/bpf/net_namespace.c 118 119 static int bpf_netns_link_fill_info(const struct bpf_link *link, 120 struct bpf_link_info *info) 121 { 122 const struct bpf_netns_link *net_link; 123 unsigned int inum; 124 struct net *net; 125 126 net_link = container_of(link, struct bpf_netns_link, link); 127 128 rcu_read_lock(); 129 net = rcu_dereference(net_link->net); 131 inum = net->ns.inum; 132 rcu_read_unlock(); 133 134 info->netns.netns_ino = inum; 135 info->netns.attach_type = net_link->type; 136 return 0; 137 } 138 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org