Hi Baolin, I love your patch! Yet something to improve: [auto build test ERROR on hnaz-mm/master] [also build test ERROR on v5.15 next-20211111] [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/Baolin-Wang/Support-multiple-tar... base: https://github.com/hnaz/linux-mm master config: m68k-allyesconfig (attached as .config) compiler: m68k-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/fda28dda2298e1ef984376940071c8435... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Baolin-Wang/Support-multiple-target-nodes-demotion/20211111-154935 git checkout fda28dda2298e1ef984376940071c8435e9b1399 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=m68k 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 >>): 1159 | static unsigned short target_nodes_max; | ^~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors vim +/target_nodes_max +1159 mm/migrate.c 1157 1158 static struct demotion_nodes *node_demotion[MAX_NUMNODES] __read_mostly; 1160 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org