tree: https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git io_uring-5.6 head: b991f4b15521532bb9754c8c41a3856d525ab8eb commit: 9a9f718763cf29faf018687b05cc0aac434fe2b8 [3/11] eventfd: track eventfd_signal() recursion depth config: s390-defconfig (attached as .config) compiler: s390-linux-gcc (GCC) 7.5.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross git checkout 9a9f718763cf29faf018687b05cc0aac434fe2b8 # save the attached .config to linux build tree GCC_VERSION=7.5.0 make.cross ARCH=s390 If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): In file included from drivers/vhost/vhost.c:13:0: include/linux/eventfd.h:43:22: error: unknown type name 'eventfd_wake_count' DECLARE_PER_CPU(int, eventfd_wake_count); ^~~~~~~~~~~~~~~~~~ include/linux/eventfd.h: In function 'eventfd_signal_count': return this_cpu_read(eventfd_wake_count); ^~~~~~~~~~~~~ test_cpu_flag include/linux/eventfd.h:47:23: error: 'eventfd_wake_count' undeclared (first use in this function); did you mean 'eventfd_signal_count'? return this_cpu_read(eventfd_wake_count); ^~~~~~~~~~~~~~~~~~ eventfd_signal_count include/linux/eventfd.h:47:23: note: each undeclared identifier is reported only once for each function it appears in cc1: some warnings being treated as errors vim +47 include/linux/eventfd.h 44 45 static inline bool eventfd_signal_count(void) 46 { 48 } 49 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation