tree: https://git.kernel.org/pub/scm/linux/kernel/git/rui/linux.git amd-pstate-dev-v1 head: abfcbc164c1aa0c63d5e256854bad977a9645586 commit: 54beca4738acc38c08710cfcb1c3312755000cf6 [5/19] cpufreq: amd: add fast switch function for amd-pstate module 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; New smatch warnings: drivers/cpufreq/amd-pstate.c:243 amd_pstate_adjust_perf() error: uninitialized symbol 'amd_des_perf'. drivers/cpufreq/amd-pstate.c:270 amd_pstate_fast_switch() warn: should 'amd_des_perf << 10' be a 64 bit type? Old smatch warnings: drivers/cpufreq/amd-pstate.c:301 amd_get_max_freq() warn: should 'max_perf << 10' be a 64 bit type? drivers/cpufreq/amd-pstate.c:342 amd_get_lowest_nonlinear_freq() warn: should 'lowest_nonlinear_perf << 10' be a 64 bit type? vim +/amd_des_perf +243 drivers/cpufreq/amd-pstate.c 54beca4738acc3 Huang Rui 2021-08-13 215 static void amd_pstate_adjust_perf(unsigned int cpu, 54beca4738acc3 Huang Rui 2021-08-13 216 unsigned long min_perf, 54beca4738acc3 Huang Rui 2021-08-13 217 unsigned long target_perf, 54beca4738acc3 Huang Rui 2021-08-13 218 unsigned long capacity) 54beca4738acc3 Huang Rui 2021-08-13 219 { 54beca4738acc3 Huang Rui 2021-08-13 220 unsigned long amd_max_perf, amd_min_perf, amd_des_perf, 54beca4738acc3 Huang Rui 2021-08-13 221 amd_cap_perf, lowest_nonlinear_perf; 54beca4738acc3 Huang Rui 2021-08-13 222 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); 54beca4738acc3 Huang Rui 2021-08-13 223 struct amd_cpudata *cpudata = policy->driver_data; 54beca4738acc3 Huang Rui 2021-08-13 224 54beca4738acc3 Huang Rui 2021-08-13 225 amd_cap_perf = READ_ONCE(cpudata->highest_perf); 54beca4738acc3 Huang Rui 2021-08-13 226 lowest_nonlinear_perf = READ_ONCE(cpudata->lowest_nonlinear_perf); 54beca4738acc3 Huang Rui 2021-08-13 227 54beca4738acc3 Huang Rui 2021-08-13 228 if (target_perf < capacity) 54beca4738acc3 Huang Rui 2021-08-13 229 amd_des_perf = DIV_ROUND_UP(amd_cap_perf * target_perf, 54beca4738acc3 Huang Rui 2021-08-13 230 capacity); Not initialized on else path. 54beca4738acc3 Huang Rui 2021-08-13 231 54beca4738acc3 Huang Rui 2021-08-13 232 amd_min_perf = READ_ONCE(cpudata->highest_perf); 54beca4738acc3 Huang Rui 2021-08-13 233 if (min_perf < capacity) 54beca4738acc3 Huang Rui 2021-08-13 234 amd_min_perf = DIV_ROUND_UP(amd_cap_perf * min_perf, capacity); 54beca4738acc3 Huang Rui 2021-08-13 235 54beca4738acc3 Huang Rui 2021-08-13 236 if (amd_min_perf < lowest_nonlinear_perf) 54beca4738acc3 Huang Rui 2021-08-13 237 amd_min_perf = lowest_nonlinear_perf; 54beca4738acc3 Huang Rui 2021-08-13 238 54beca4738acc3 Huang Rui 2021-08-13 239 amd_max_perf = amd_cap_perf; 54beca4738acc3 Huang Rui 2021-08-13 240 if (amd_max_perf < amd_min_perf) 54beca4738acc3 Huang Rui 2021-08-13 241 amd_max_perf = amd_min_perf; 54beca4738acc3 Huang Rui 2021-08-13 242 54beca4738acc3 Huang Rui 2021-08-13 @243 amd_des_perf = clamp_t(unsigned long, amd_des_perf, ^^^^^^^^^^^^ Uninitialized. 54beca4738acc3 Huang Rui 2021-08-13 244 amd_min_perf, amd_max_perf); 54beca4738acc3 Huang Rui 2021-08-13 245 54beca4738acc3 Huang Rui 2021-08-13 246 amd_pstate_update(cpudata, amd_min_perf, amd_des_perf, 54beca4738acc3 Huang Rui 2021-08-13 247 amd_max_perf, true); 54beca4738acc3 Huang Rui 2021-08-13 248 } 54beca4738acc3 Huang Rui 2021-08-13 249 54beca4738acc3 Huang Rui 2021-08-13 250 static unsigned int amd_pstate_fast_switch(struct cpufreq_policy *policy, 54beca4738acc3 Huang Rui 2021-08-13 251 unsigned int target_freq) 54beca4738acc3 Huang Rui 2021-08-13 252 { 54beca4738acc3 Huang Rui 2021-08-13 253 u64 ratio; 54beca4738acc3 Huang Rui 2021-08-13 254 struct amd_cpudata *cpudata = policy->driver_data; 54beca4738acc3 Huang Rui 2021-08-13 255 unsigned long amd_max_perf, amd_min_perf, amd_des_perf, nominal_perf; 54beca4738acc3 Huang Rui 2021-08-13 256 54beca4738acc3 Huang Rui 2021-08-13 257 if (!cpudata->max_freq) 54beca4738acc3 Huang Rui 2021-08-13 258 return -ENODEV; 54beca4738acc3 Huang Rui 2021-08-13 259 54beca4738acc3 Huang Rui 2021-08-13 260 amd_max_perf = READ_ONCE(cpudata->highest_perf); 54beca4738acc3 Huang Rui 2021-08-13 261 amd_min_perf = READ_ONCE(cpudata->lowest_nonlinear_perf); 54beca4738acc3 Huang Rui 2021-08-13 262 54beca4738acc3 Huang Rui 2021-08-13 263 amd_des_perf = DIV_ROUND_UP(target_freq * amd_max_perf, 54beca4738acc3 Huang Rui 2021-08-13 264 cpudata->max_freq); 54beca4738acc3 Huang Rui 2021-08-13 265 54beca4738acc3 Huang Rui 2021-08-13 266 amd_pstate_update(cpudata, amd_min_perf, amd_des_perf, 54beca4738acc3 Huang Rui 2021-08-13 267 amd_max_perf, true); 54beca4738acc3 Huang Rui 2021-08-13 268 54beca4738acc3 Huang Rui 2021-08-13 269 nominal_perf = READ_ONCE(cpudata->nominal_perf); 54beca4738acc3 Huang Rui 2021-08-13 @270 ratio = div_u64(amd_des_perf << SCHED_CAPACITY_SHIFT, nominal_perf); Should amd_des_perf be a u64? Does that matter on 32 bit systems? 54beca4738acc3 Huang Rui 2021-08-13 271 54beca4738acc3 Huang Rui 2021-08-13 272 return cpudata->nominal_freq * ratio >> SCHED_CAPACITY_SHIFT; 54beca4738acc3 Huang Rui 2021-08-13 273 } --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org