[kbuild-all] [rui:amd-pstate-dev-v1 4/19] drivers/cpufreq/amd-pstate.c:241 amd_get_max_freq() warn: should 'max_perf << 10' be a 64 bit type?

tree: https://git.kernel.org/pub/scm/linux/kernel/git/rui/linux.git amd-pstate-dev-v1 head: abfcbc164c1aa0c63d5e256854bad977a9645586 commit: df9ad0b99a9f0e3371aa94e49fe92a2c2a9fa95d [4/19] cpufreq: amd: introduce a new amd pstate driver to support future processors config: i386-randconfig-m021-20210912 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; smatch warnings: drivers/cpufreq/amd-pstate.c:241 amd_get_max_freq() warn: should 'max_perf << 10' be a 64 bit type? drivers/cpufreq/amd-pstate.c:282 amd_get_lowest_nonlinear_freq() warn: should 'lowest_nonlinear_perf << 10' be a 64 bit type? vim +241 drivers/cpufreq/amd-pstate.c df9ad0b99a9f0e Huang Rui 2021-06-10 227 static int amd_get_max_freq(struct amd_cpudata *cpudata) df9ad0b99a9f0e Huang Rui 2021-06-10 228 { df9ad0b99a9f0e Huang Rui 2021-06-10 229 struct cppc_perf_caps cppc_perf; df9ad0b99a9f0e Huang Rui 2021-06-10 230 u32 max_perf, max_freq, nominal_freq, nominal_perf; df9ad0b99a9f0e Huang Rui 2021-06-10 231 u64 boost_ratio; df9ad0b99a9f0e Huang Rui 2021-06-10 232 df9ad0b99a9f0e Huang Rui 2021-06-10 233 int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); df9ad0b99a9f0e Huang Rui 2021-06-10 234 if (ret) df9ad0b99a9f0e Huang Rui 2021-06-10 235 return ret; df9ad0b99a9f0e Huang Rui 2021-06-10 236 df9ad0b99a9f0e Huang Rui 2021-06-10 237 nominal_freq = cppc_perf.nominal_freq; df9ad0b99a9f0e Huang Rui 2021-06-10 238 nominal_perf = READ_ONCE(cpudata->nominal_perf); df9ad0b99a9f0e Huang Rui 2021-06-10 239 max_perf = READ_ONCE(cpudata->highest_perf); df9ad0b99a9f0e Huang Rui 2021-06-10 240 df9ad0b99a9f0e Huang Rui 2021-06-10 @241 boost_ratio = div_u64(max_perf << SCHED_CAPACITY_SHIFT, df9ad0b99a9f0e Huang Rui 2021-06-10 242 nominal_perf); Presumably the max_perf << SCHED_CAPACITY_SHIFT shift can wrap. The "max_perf" variable should probably be declared as a u64. I will also create a new static checker warning specifically for when div_u64() is used on a u32. df9ad0b99a9f0e Huang Rui 2021-06-10 243 df9ad0b99a9f0e Huang Rui 2021-06-10 244 max_freq = nominal_freq * boost_ratio >> SCHED_CAPACITY_SHIFT; df9ad0b99a9f0e Huang Rui 2021-06-10 245 df9ad0b99a9f0e Huang Rui 2021-06-10 246 /* Switch to khz */ df9ad0b99a9f0e Huang Rui 2021-06-10 247 return max_freq * 1000; df9ad0b99a9f0e Huang Rui 2021-06-10 248 } df9ad0b99a9f0e Huang Rui 2021-06-10 249 df9ad0b99a9f0e Huang Rui 2021-06-10 250 static int amd_get_nominal_freq(struct amd_cpudata *cpudata) df9ad0b99a9f0e Huang Rui 2021-06-10 251 { df9ad0b99a9f0e Huang Rui 2021-06-10 252 struct cppc_perf_caps cppc_perf; df9ad0b99a9f0e Huang Rui 2021-06-10 253 u32 nominal_freq; df9ad0b99a9f0e Huang Rui 2021-06-10 254 df9ad0b99a9f0e Huang Rui 2021-06-10 255 int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); df9ad0b99a9f0e Huang Rui 2021-06-10 256 if (ret) df9ad0b99a9f0e Huang Rui 2021-06-10 257 return ret; df9ad0b99a9f0e Huang Rui 2021-06-10 258 df9ad0b99a9f0e Huang Rui 2021-06-10 259 nominal_freq = cppc_perf.nominal_freq; df9ad0b99a9f0e Huang Rui 2021-06-10 260 df9ad0b99a9f0e Huang Rui 2021-06-10 261 /* Switch to khz */ df9ad0b99a9f0e Huang Rui 2021-06-10 262 return nominal_freq * 1000; df9ad0b99a9f0e Huang Rui 2021-06-10 263 } df9ad0b99a9f0e Huang Rui 2021-06-10 264 df9ad0b99a9f0e Huang Rui 2021-06-10 265 static int amd_get_lowest_nonlinear_freq(struct amd_cpudata *cpudata) df9ad0b99a9f0e Huang Rui 2021-06-10 266 { df9ad0b99a9f0e Huang Rui 2021-06-10 267 struct cppc_perf_caps cppc_perf; df9ad0b99a9f0e Huang Rui 2021-06-10 268 u32 lowest_nonlinear_freq, lowest_nonlinear_perf, df9ad0b99a9f0e Huang Rui 2021-06-10 269 nominal_freq, nominal_perf; df9ad0b99a9f0e Huang Rui 2021-06-10 270 u64 lowest_nonlinear_ratio; df9ad0b99a9f0e Huang Rui 2021-06-10 271 df9ad0b99a9f0e Huang Rui 2021-06-10 272 int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf); df9ad0b99a9f0e Huang Rui 2021-06-10 273 if (ret) df9ad0b99a9f0e Huang Rui 2021-06-10 274 return ret; df9ad0b99a9f0e Huang Rui 2021-06-10 275 df9ad0b99a9f0e Huang Rui 2021-06-10 276 nominal_freq = cppc_perf.nominal_freq; df9ad0b99a9f0e Huang Rui 2021-06-10 277 nominal_perf = READ_ONCE(cpudata->nominal_perf); df9ad0b99a9f0e Huang Rui 2021-06-10 278 df9ad0b99a9f0e Huang Rui 2021-06-10 279 lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf; df9ad0b99a9f0e Huang Rui 2021-06-10 280 df9ad0b99a9f0e Huang Rui 2021-06-10 281 lowest_nonlinear_ratio = div_u64(lowest_nonlinear_perf << df9ad0b99a9f0e Huang Rui 2021-06-10 @282 SCHED_CAPACITY_SHIFT, nominal_perf); Same. df9ad0b99a9f0e Huang Rui 2021-06-10 283 df9ad0b99a9f0e Huang Rui 2021-06-10 284 lowest_nonlinear_freq = nominal_freq * lowest_nonlinear_ratio >> SCHED_CAPACITY_SHIFT; df9ad0b99a9f0e Huang Rui 2021-06-10 285 df9ad0b99a9f0e Huang Rui 2021-06-10 286 /* Switch to khz */ df9ad0b99a9f0e Huang Rui 2021-06-10 287 return lowest_nonlinear_freq * 1000; df9ad0b99a9f0e Huang Rui 2021-06-10 288 } --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org