Hi SeongJae, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on hnaz-mm/master] [also build test WARNING on shuah-kselftest/next linux/master linus/master v5.17-rc4 next-20220217] [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/SeongJae-Park/Introduce-DAMON-sy... base: https://github.com/hnaz/linux-mm master config: arc-allyesconfig (https://download.01.org/0day-ci/archive/20220218/202202180207.cMG3IvJT-lk...) compiler: arceb-elf-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/f0b638f2a815dfdba8e4164563e21f774... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review SeongJae-Park/Introduce-DAMON-sysfs-interface/20220218-002109 git checkout f0b638f2a815dfdba8e4164563e21f7744becda5 # 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=arc SHELL=/bin/bash mm/damon/ 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 >>): 898 | int damon_sysfs_nr_running_ctxs(struct damon_sysfs_kdamond **kdamonds, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ vim +/damon_sysfs_nr_running_ctxs +898 mm/damon/sysfs.c 897 899 int nr_kdamonds) 900 { 901 int nr_running_ctxs = 0; 902 int i; 903 904 for (i = 0; i < nr_kdamonds; i++) { 905 struct damon_ctx *ctx; 906 907 ctx = kdamonds[i]->damon_ctx; 908 if (!ctx) 909 continue; 910 mutex_lock(&ctx->kdamond_lock); 911 if (ctx->kdamond) 912 nr_running_ctxs++; 913 mutex_unlock(&ctx->kdamond_lock); 914 } 915 return nr_running_ctxs; 916 } 917 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org