Hi Jinchao, kernel test robot noticed the following build warnings:
[auto build test WARNING on akpm-mm/mm-everything] url: https://github.com/intel-lab-lkp/linux/commits/Jinchao-Wang/mm-ksw-add-build-system-support/20250904-082544 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/20250904002126.1514566-7-wangjinchao600%40gmail.com patch subject: [PATCH v2 06/18] perf/hw_breakpoint: add arch-independent hw_breakpoint_modify_local() config: sh-randconfig-001-20250905 (https://download.01.org/0day-ci/archive/20250905/202509052351.kuhbwdaf-...@intel.com/config) compiler: sh4-linux-gcc (GCC) 15.1.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250905/202509052351.kuhbwdaf-...@intel.com/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <l...@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202509052351.kuhbwdaf-...@intel.com/ All warnings (new ones prefixed by >>): kernel/events/hw_breakpoint.c: In function 'hw_breakpoint_modify_local': kernel/events/hw_breakpoint.c:994:16: error: implicit declaration of function 'arch_reinstall_hw_breakpoint'; did you mean 'arch_uninstall_hw_breakpoint'? [-Wimplicit-function-declaration] 994 | return arch_reinstall_hw_breakpoint(bp); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ | arch_uninstall_hw_breakpoint kernel/events/hw_breakpoint.c: At top level: >> kernel/events/hw_breakpoint.c:999:12: warning: no previous prototype for >> 'arch_reinstall_hw_breakpoint' [-Wmissing-prototypes] 999 | __weak int arch_reinstall_hw_breakpoint(struct perf_event *bp) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ vim +/arch_reinstall_hw_breakpoint +999 kernel/events/hw_breakpoint.c 997 998 /* weak fallback for arches without support */ > 999 __weak int arch_reinstall_hw_breakpoint(struct perf_event *bp) 1000 { 1001 return -EOPNOTSUPP; 1002 } 1003 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
