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/20230308-112932 base: 1440f576022887004f719883acb094e7e0dd4944 patch link: https://lore.kernel.org/r/20230308032748.609510-3-nphamcs%40gmail.com patch subject: [PATCH v11 2/3] cachestat: implement cachestat syscall config: arm-randconfig-r046-20230308 (https://download.01.org/0day-ci/archive/20230309/202303092111.mhDcYB71-lkp@xxxxxxxxx/config) compiler: arm-linux-gnueabi-gcc (GCC) 12.1.0 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/intel-lab-lkp/linux/commit/ca34a4daf11f6fbb9731205af7acd06fe620e447 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/20230308-112932 git checkout ca34a4daf11f6fbb9731205af7acd06fe620e447 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash kernel/bpf/ mm/ prepare If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Link: https://lore.kernel.org/oe-kbuild-all/202303092111.mhDcYB71-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): >> <stdin>:1565:2: warning: #warning syscall cachestat not implemented [-Wcpp] -- In file included from include/linux/filter.h:11, from include/linux/bpf_verifier.h:9, from tools/lib/bpf/relo_core.c:8: >> include/linux/compat.h:821:45: warning: 'struct cachestat' declared inside parameter list will not be visible outside of this definition or declaration 821 | compat_arg_u64(off), struct cachestat __user *cstat, | ^~~~~~~~~ -- In file included from include/linux/filter.h:11, from kernel/bpf/core.c:21: >> include/linux/compat.h:821:45: warning: 'struct cachestat' declared inside parameter list will not be visible outside of this definition or declaration 821 | compat_arg_u64(off), struct cachestat __user *cstat, | ^~~~~~~~~ kernel/bpf/core.c:1628:12: warning: no previous prototype for 'bpf_probe_read_kernel' [-Wmissing-prototypes] 1628 | u64 __weak bpf_probe_read_kernel(void *dst, u32 size, const void *unsafe_ptr) | ^~~~~~~~~~~~~~~~~~~~~ -- In file included from include/linux/filter.h:11, from include/linux/bpf_verifier.h:9, from kernel/bpf/btf.c:19: >> include/linux/compat.h:821:45: warning: 'struct cachestat' declared inside parameter list will not be visible outside of this definition or declaration 821 | compat_arg_u64(off), struct cachestat __user *cstat, | ^~~~~~~~~ kernel/bpf/btf.c: In function 'btf_seq_show': kernel/bpf/btf.c:6786:29: warning: function 'btf_seq_show' might be a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format] 6786 | seq_vprintf((struct seq_file *)show->target, fmt, args); | ^~~~~~~~ kernel/bpf/btf.c: In function 'btf_snprintf_show': kernel/bpf/btf.c:6823:9: warning: function 'btf_snprintf_show' might be a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format] 6823 | len = vsnprintf(show->target, ssnprintf->len_left, fmt, args); | ^~~ -- >> mm/filemap.c:4034:6: warning: no previous prototype for 'ksys_cachestat' [-Wmissing-prototypes] 4034 | long ksys_cachestat(unsigned int fd, size_t len, loff_t off, | ^~~~~~~~~~~~~~ -- >> <stdin>:1565:2: warning: #warning syscall cachestat not implemented [-Wcpp] -- >> <stdin>:1565:2: warning: #warning syscall cachestat not implemented [-Wcpp] vim +821 include/linux/compat.h 809 810 /* net/socket.c */ 811 asmlinkage long compat_sys_recvfrom(int fd, void __user *buf, compat_size_t len, 812 unsigned flags, struct sockaddr __user *addr, 813 int __user *addrlen); 814 asmlinkage long compat_sys_sendmsg(int fd, struct compat_msghdr __user *msg, 815 unsigned flags); 816 asmlinkage long compat_sys_recvmsg(int fd, struct compat_msghdr __user *msg, 817 unsigned int flags); 818 819 /* mm/filemap.c */ 820 asmlinkage long compat_sys_cachestat(unsigned int fd, size_t len, > 821 compat_arg_u64(off), struct cachestat __user *cstat, 822 unsigned int flags); 823 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
