tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   ae83d0b416db002fe95601e7f97f64b59514d936
commit: a0f60f8431999bf57cf53c3b27c47ef156b4fa17 s390/protvirt: Add sysfs firmware interface for Ultravisor information
date:   8 weeks ago
config: s390-randconfig-a001-20200421 (attached as .config)
compiler: s390-linux-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        git checkout a0f60f8431999bf57cf53c3b27c47ef156b4fa17
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day GCC_VERSION=9.3.0 make.cross ARCH=s390 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   s390-linux-ld: arch/s390/kernel/uv.o: in function `uv_query_max_guest_addr':
>> arch/s390/kernel/uv.c:366: undefined reference to `uv_info'
>> s390-linux-ld: arch/s390/kernel/uv.c:366: undefined reference to `uv_info'
   s390-linux-ld: arch/s390/kernel/uv.o: in function `uv_query_max_guest_vms':
   arch/s390/kernel/uv.c:356: undefined reference to `uv_info'
   s390-linux-ld: arch/s390/kernel/uv.c:356: undefined reference to `uv_info'
   s390-linux-ld: arch/s390/kernel/uv.o: in function `uv_query_max_guest_cpus':
   arch/s390/kernel/uv.c:347: undefined reference to `uv_info'
   s390-linux-ld: arch/s390/kernel/uv.o:arch/s390/kernel/uv.c:347: more undefined references to `uv_info' follow

vim +366 arch/s390/kernel/uv.c

   359	
   360	static struct kobj_attribute uv_query_max_guest_vms_attr =
   361		__ATTR(max_guests, 0444, uv_query_max_guest_vms, NULL);
   362	
   363	static ssize_t uv_query_max_guest_addr(struct kobject *kobj,
   364					       struct kobj_attribute *attr, char *page)
   365	{
 > 366		return snprintf(page, PAGE_SIZE, "%lx\n",
   367				uv_info.max_sec_stor_addr);
   368	}
   369	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org