tree: https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git queue-4.4 head: 0403535f41a8ea7e98d76c506e9425d357c670c3 commit: dbcde903799671b0c171e0450733faaf11dc66ad [7/10] s390/smp: use smp_get_base_cpu() helper function config: s390-allyesconfig (attached as .config) compiler: s390-linux-gcc (GCC) 7.5.0 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://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git/c... git remote add sashal-linux-stable https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git git fetch --no-tags sashal-linux-stable queue-4.4 git checkout dbcde903799671b0c171e0450733faaf11dc66ad # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-7.5.0 make.cross ARCH=s390 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): arch/s390/kernel/smp.c: In function '__cpu_up': base = smp_get_base_cpu(cpu); ^~~~~~~~~~~~~~~~ set_task_cpu cc1: some warnings being treated as errors vim +852 arch/s390/kernel/smp.c 842 843 /* Upping and downing of CPUs */ 844 int __cpu_up(unsigned int cpu, struct task_struct *tidle) 845 { 846 struct pcpu *pcpu; 847 int base, i, rc; 848 849 pcpu = pcpu_devices + cpu; 850 if (pcpu->state != CPU_STATE_CONFIGURED) 851 return -EIO; 853 for (i = 0; i <= smp_cpu_mtid; i++) { 854 if (base + i < nr_cpu_ids) 855 if (cpu_online(base + i)) 856 break; 857 } 858 /* 859 * If this is the first CPU of the core to get online 860 * do an initial CPU reset. 861 */ 862 if (i > smp_cpu_mtid && 863 pcpu_sigp_retry(pcpu_devices + base, SIGP_INITIAL_CPU_RESET, 0) != 864 SIGP_CC_ORDER_CODE_ACCEPTED) 865 return -EIO; 866 867 rc = pcpu_alloc_lowcore(pcpu, cpu); 868 if (rc) 869 return rc; 870 pcpu_prepare_secondary(pcpu, cpu); 871 pcpu_attach_task(pcpu, tidle); 872 pcpu_start_fn(pcpu, smp_start_secondary, NULL); 873 /* Wait until cpu puts itself in the online & active maps */ 874 while (!cpu_online(cpu) || !cpu_active(cpu)) 875 cpu_relax(); 876 return 0; 877 } 878 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org