Hi Nhat, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on 1440f576022887004f719883acb094e7e0dd4944] url: https://github.com/intel-lab-lkp/linux/commits/Nhat-Pham/workingset-refactor-LRU-refault-to-expose-refault-recency-check/20230204-030455 base: 1440f576022887004f719883acb094e7e0dd4944 patch link: https://lore.kernel.org/r/20230203190413.2559707-3-nphamcs%40gmail.com patch subject: [PATCH v9 2/3] cachestat: implement cachestat syscall config: i386-allnoconfig (https://download.01.org/0day-ci/archive/20230204/202302040546.JHm5vnYB-lkp@xxxxxxxxx/config) compiler: gcc-11 (Debian 11.3.0-8) 11.3.0 reproduce (this is a W=1 build): # https://github.com/intel-lab-lkp/linux/commit/49a57ed71ac2c005231660c85c3f30c4b47d8b7b git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Nhat-Pham/workingset-refactor-LRU-refault-to-expose-refault-recency-check/20230204-030455 git checkout 49a57ed71ac2c005231660c85c3f30c4b47d8b7b # save the config file mkdir build_dir && cp config build_dir/.config make W=1 O=build_dir ARCH=i386 olddefconfig make W=1 O=build_dir ARCH=i386 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/filemap.c:4035:6: warning: no previous prototype for 'ksys_cachestat' [-Wmissing-prototypes] 4035 | long ksys_cachestat(unsigned int fd, loff_t off, size_t len, | ^~~~~~~~~~~~~~ vim +/ksys_cachestat +4035 mm/filemap.c 4033 4034 #ifdef CONFIG_CACHESTAT_SYSCALL > 4035 long ksys_cachestat(unsigned int fd, loff_t off, size_t len, 4036 struct cachestat __user *cstat, unsigned int flags) 4037 { 4038 struct fd f = fdget(fd); 4039 struct address_space *mapping; 4040 struct cachestat cs; 4041 pgoff_t first_index = off >> PAGE_SHIFT; 4042 pgoff_t last_index = 4043 len == 0 ? ULONG_MAX : (off + len - 1) >> PAGE_SHIFT; 4044 4045 if (!f.file) 4046 return -EBADF; 4047 4048 if (off < 0 || flags != 0) { 4049 fdput(f); 4050 return -EINVAL; 4051 } 4052 4053 memset(&cs, 0, sizeof(struct cachestat)); 4054 mapping = f.file->f_mapping; 4055 filemap_cachestat(mapping, first_index, last_index, &cs); 4056 fdput(f); 4057 4058 if (copy_to_user(cstat, &cs, sizeof(struct cachestat))) 4059 return -EFAULT; 4060 4061 return 0; 4062 } 4063 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
