Hi hezhongkun, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v5.18 next-20220524] [cannot apply to akpm-mm/mm-everything] [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/intel-lab-lkp/linux/commits/hezhongkun/mm-memcontrol-add-the-mempolicy-interface-for-cgroup-v2/20220524-183922 base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 143a6252e1b8ab424b4b293512a97cca7295c182 config: x86_64-randconfig-a014 (https://download.01.org/0day-ci/archive/20220524/202205242316.8f8rvh3s-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 10c9ecce9f6096e18222a331c5e7d085bd813f75) 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/intel-lab-lkp/linux/commit/6adb0a02c27c8811bee9783451ee25155baf490e git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review hezhongkun/mm-memcontrol-add-the-mempolicy-interface-for-cgroup-v2/20220524-183922 git checkout 6adb0a02c27c8811bee9783451ee25155baf490e # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> mm/mempolicy.c:179:19: warning: no previous prototype for function 'get_cgrp_or_task_policy' [-Wmissing-prototypes] struct mempolicy *get_cgrp_or_task_policy(struct task_struct *p) ^ mm/mempolicy.c:179:1: note: declare 'static' if the function is not intended to be used outside of this translation unit struct mempolicy *get_cgrp_or_task_policy(struct task_struct *p) ^ static 1 warning generated. vim +/get_cgrp_or_task_policy +179 mm/mempolicy.c 178 > 179 struct mempolicy *get_cgrp_or_task_policy(struct task_struct *p) 180 { 181 struct mempolicy *pol; 182 struct mem_cgroup *memcg = mem_cgroup_from_task(p); 183 184 pol = (memcg && memcg->mempolicy) ? memcg->mempolicy : get_task_policy(p); 185 return pol; 186 } 187 -- 0-DAY CI Kernel Test Service https://01.org/lkp