tree: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git master head: 5765cee119bf5a36c94d20eceb37c445508934be commit: 79074a72d335dbd021a716d8cc65cba3b2f706ab [63/65] net: Flush deferred skb free on socket destroy config: csky-randconfig-r035-20220117 (https://download.01.org/0day-ci/archive/20220118/202201180610.noKfNl47-lk...) compiler: csky-linux-gcc (GCC) 11.2.0 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/davem/net.git/commit/?id=... git remote add net https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git git fetch --no-tags net master git checkout 79074a72d335dbd021a716d8cc65cba3b2f706ab # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=csky SHELL=/bin/bash 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 >>): csky-linux-ld: net/core/sock.o: in function `sk_destruct': sock.c:(.text+0x1780): undefined reference to `__sk_defer_free_flush' --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org