tree: https://github.com/thierryreding/linux for-5.13/work head: 009ea3ee74a12859073a37d2ef800fa154ff7705 commit: f3d8000cf65d974c4b59bdb20f72a7b2af0260de [45/49] early_tcu config: mips-allyesconfig (attached as .config) compiler: mips-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/thierryreding/linux/commit/f3d8000cf65d974c4b59bdb20f7... git remote add thierryreding https://github.com/thierryreding/linux git fetch --no-tags thierryreding for-5.13/work git checkout f3d8000cf65d974c4b59bdb20f72a7b2af0260de # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=mips 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 >>): 62 | int __init early_tegra_combined_uart_setup(struct earlycon_device *device, const char *options) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ vim +/early_tegra_combined_uart_setup +62 drivers/tty/serial/tegra-tcu-earlycon.c 61 63 { 64 if (!(device->port.membase)) 65 return -ENODEV; 66 67 device->con->write = early_tcu_write; 68 69 return 0; 70 } 71 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org