tree: https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git ptp-1588-optional head: 3f69b7366cfd4b2c048c76be5299b38066933ee1 commit: 3f69b7366cfd4b2c048c76be5299b38066933ee1 [1/1] ethernet: fix PTP_1588_CLOCK dependencies config: m68k-defconfig (attached as .config) compiler: m68k-linux-gcc (GCC) 10.3.0 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/arnd/playground.git/commit/?id=3f69b7366cfd4b2c048c76be5299b38066933ee1 git remote add arnd-playground https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git git fetch --no-tags arnd-playground ptp-1588-optional git checkout 3f69b7366cfd4b2c048c76be5299b38066933ee1 # save the attached .config to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross O=build_dir ARCH=m68k SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>): m68k-linux-ld: net/socket.o: in function `__sock_recv_timestamp': >> socket.c:(.text+0x1204): undefined reference to `ptp_convert_timestamp' m68k-linux-ld: net/ethtool/common.o: in function `ethtool_get_phc_vclocks': >> common.c:(.text+0x370): undefined reference to `ptp_get_vclocks_index' --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org