Hi Atish, FYI, the error/warning still remains. tree: https://github.com/ammarfaizi2/linux-block palmer/linux/riscv-pmu head: 7a94c6fb363cfe62906cb0503d763204b0fe32b8 commit: e4d5f33e63b1260f378512c0f6e5a117ed6b894a [4/10] RISC-V: Add a simple platform driver for RISC-V legacy perf config: riscv-randconfig-r042-20211213 (https://download.01.org/0day-ci/archive/20220311/202203110927.3ArrLPWM-lkp@xxxxxxxxx/config) compiler: riscv64-linux-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/ammarfaizi2/linux-block/commit/e4d5f33e63b1260f378512c0f6e5a117ed6b894a git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block git fetch --no-tags ammarfaizi2-block palmer/linux/riscv-pmu git checkout e4d5f33e63b1260f378512c0f6e5a117ed6b894a # 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=riscv SHELL=/bin/bash drivers/perf/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> drivers/perf/riscv_pmu_legacy.c:76: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * This is just a simple implementation to allow legacy implementations vim +76 drivers/perf/riscv_pmu_legacy.c 74 75 /** > 76 * This is just a simple implementation to allow legacy implementations 77 * compatible with new RISC-V PMU driver framework. 78 * This driver only allows reading two counters i.e CYCLE & INSTRET. 79 * However, it can not start or stop the counter. Thus, it is not very useful 80 * will be removed in future. 81 */ 82 static void pmu_legacy_init(struct riscv_pmu *pmu) 83 { 84 pr_info("Legacy PMU implementation is available\n"); 85 86 pmu->num_counters = RISCV_PMU_LEGACY_NUM_CTR; 87 pmu->ctr_start = pmu_legacy_ctr_start; 88 pmu->ctr_stop = NULL; 89 pmu->event_map = pmu_legacy_event_map; 90 pmu->ctr_get_idx = pmu_legacy_ctr_get_idx; 91 pmu->ctr_get_width = NULL; 92 pmu->ctr_clear_idx = NULL; 93 pmu->ctr_read = pmu_legacy_read_ctr; 94 95 perf_pmu_register(&pmu->pmu, "cpu", PERF_TYPE_RAW); 96 } 97 --- 0-DAY CI Kernel Test Service https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx