Hi Nicholas, I love your patch! Perhaps something to improve: [auto build test WARNING on powerpc/next] [also build test WARNING on v5.15 next-20211111] [cannot apply to scottwood/next] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Nicholas-Piggin/powerpc-64s-Get-LPID-bit-width-from-device-tree/20211110-160038 base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next config: powerpc64-buildonly-randconfig-r001-20211111 (attached as .config) compiler: powerpc64le-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/b8fe7181506bf3011295456a9ee471ddf49d694d git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Nicholas-Piggin/powerpc-64s-Get-LPID-bit-width-from-device-tree/20211110-160038 git checkout b8fe7181506bf3011295456a9ee471ddf49d694d # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=powerpc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): arch/powerpc/mm/init_64.c: In function 'mmu_early_init_devtree': >> arch/powerpc/mm/init_64.c:472:13: warning: variable 'rc' set but not used [-Wunused-but-set-variable] 472 | int rc; | ^~ vim +/rc +472 arch/powerpc/mm/init_64.c 469 470 void __init mmu_early_init_devtree(void) 471 { > 472 int rc; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org