Hi Richard, [FYI, it's a private test report for your RFC patch.] [auto build test ERROR on net-next/master] url: https://github.com/0day-ci/linux/commits/Richard-Cochran/Make-MAC-PHY-time-stamping-selectable/20220104-072717 base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 3d694552fd8fe502e7ffd22ffa0e085bfd73b19a config: parisc-defconfig (https://download.01.org/0day-ci/archive/20220104/202201041412.WPk0XCA0-lkp(a)intel.com/config) compiler: hppa-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://github.com/0day-ci/linux/commit/33070417b78b3844a2b2f55f94313072859da977 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Richard-Cochran/Make-MAC-PHY-time-stamping-selectable/20220104-072717 git checkout 33070417b78b3844a2b2f55f94313072859da977 # 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=parisc 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 >>): hppa-linux-ld: net/core/dev_ioctl.o: in function `dev_ifsioc': >> (.text+0x1b0): undefined reference to `phy_mii_ioctl' hppa-linux-ld: net/core/dev_ioctl.o: in function `.LC2': >> (.rodata.cst4+0x0): undefined reference to `phy_do_ioctl' --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org