Hi Liangliang, FYI, the error/warning still remains. tree: https://android.googlesource.com/kernel/common android13-5.10 head: c2a29c3b6e4e5f177d23d0d006b0bebe3e1bc600 commit: 372b24bad2a8e7994d0360c870f6e981e3f4bb8f [10184/16048] ANDROID: GKI: Add OEM data to mutex/rwsem config: arm-buildonly-randconfig-r005-20211103 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 264d3b6d4e08401c5b50a85bd76e80b3461d77e6) 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 # install arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi git remote add android-common https://android.googlesource.com/kernel/common git fetch --no-tags android-common android13-5.10 git checkout 372b24bad2a8e7994d0360c870f6e981e3f4bb8f # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=arm If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): drivers/cpufreq/s3c24xx-cpufreq.c:88:19: warning: unused function 'closer' [-Wunused-function] static inline int closer(unsigned int target, unsigned int n, unsigned int c) ^ static int s3c_cpufreq_target(struct cpufreq_policy *policy, ^ 2 warnings generated. vim +/s3c_cpufreq_target +270 drivers/cpufreq/s3c24xx-cpufreq.c 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 263 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 264 /* s3c_cpufreq_target 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 265 * 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 266 * called by the cpufreq core to adjust the frequency that the CPU 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 267 * is currently running at. 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 268 */ 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 269 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 @270 static int s3c_cpufreq_target(struct cpufreq_policy *policy, 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 271 unsigned int target_freq, 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 272 unsigned int relation) 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 273 { 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 274 struct cpufreq_frequency_table *pll; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 275 unsigned int index; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 276 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 277 /* avoid repeated calls which cause a needless amout of duplicated 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 278 * logging output (and CPU time as the calculation process is 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 279 * done) */ 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 280 if (target_freq == last_target) 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 281 return 0; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 282 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 283 last_target = target_freq; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 284 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 285 s3c_freq_dbg("%s: policy %p, target %u, relation %u\n", 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 286 __func__, policy, target_freq, relation); 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 287 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 288 if (ftab) { d218ed773915a2 drivers/cpufreq/s3c24xx-cpufreq.c Viresh Kumar 2016-06-03 289 index = cpufreq_frequency_table_target(policy, target_freq, d218ed773915a2 drivers/cpufreq/s3c24xx-cpufreq.c Viresh Kumar 2016-06-03 290 relation); 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 291 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 292 s3c_freq_dbg("%s: adjust %d to entry %d (%u)\n", __func__, 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 293 target_freq, index, ftab[index].frequency); 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 294 target_freq = ftab[index].frequency; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 295 } 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 296 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 297 target_freq *= 1000; /* convert target to Hz */ 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 298 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 299 /* find the settings for our new frequency */ 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 300 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 301 if (!pll_reg || cpu_cur.lock_pll) { 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 302 /* either we've not got any PLL values, or we've locked 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 303 * to the current one. */ 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 304 pll = NULL; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 305 } else { 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 306 struct cpufreq_policy tmp_policy; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 307 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 308 /* we keep the cpu pll table in Hz, to ensure we get an 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 309 * accurate value for the PLL output. */ 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 310 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 311 tmp_policy.min = policy->min * 1000; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 312 tmp_policy.max = policy->max * 1000; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 313 tmp_policy.cpu = policy->cpu; 7ab4aabbaa98fb drivers/cpufreq/s3c24xx-cpufreq.c Viresh Kumar 2016-06-03 314 tmp_policy.freq_table = pll_reg; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 315 d218ed773915a2 drivers/cpufreq/s3c24xx-cpufreq.c Viresh Kumar 2016-06-03 316 /* cpufreq_frequency_table_target returns the index d218ed773915a2 drivers/cpufreq/s3c24xx-cpufreq.c Viresh Kumar 2016-06-03 317 * of the table entry, not the value of 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 318 * the table entry's index field. */ 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 319 d218ed773915a2 drivers/cpufreq/s3c24xx-cpufreq.c Viresh Kumar 2016-06-03 320 index = cpufreq_frequency_table_target(&tmp_policy, target_freq, d218ed773915a2 drivers/cpufreq/s3c24xx-cpufreq.c Viresh Kumar 2016-06-03 321 relation); 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 322 pll = pll_reg + index; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 323 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 324 s3c_freq_dbg("%s: target %u => %u\n", 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 325 __func__, target_freq, pll->frequency); 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 326 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 327 target_freq = pll->frequency; 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 328 } 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 329 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 330 return s3c_cpufreq_settarget(policy, target_freq, pll); 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 331 } 2e4ea6e8209e0c arch/arm/plat-s3c24xx/cpu-freq.c Ben Dooks 2009-07-30 332 :::::: The code at line 270 was first introduced by commit :::::: 2e4ea6e8209e0c1d93c69c34c32002337b3f747e ARM: S3C24XX: CPUFREQ: Add core support. :::::: TO: Ben Dooks <ben(a)simtec.co.uk&gt; :::::: CC: Ben Dooks <ben-linux(a)fluff.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org