Hi Anshuman, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on v5.10-rc6] [cannot apply to mmotm/master s390/features arm64/for-next/core hnaz-linux-mm/master next-20201127] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Anshuman-Khandual/mm-hotplug-Pre... base: b65054597872ce3aefbc6a666385eabdf9e288da config: s390-randconfig-r024-20201130 (attached as .config) compiler: s390-linux-gcc (GCC) 9.3.0 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://github.com/0day-ci/linux/commit/07c7b752176c2d810fc3dc44f9b41593d... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Anshuman-Khandual/mm-hotplug-Pre-validate-the-address-range-with-platform/20201130-113145 git checkout 07c7b752176c2d810fc3dc44f9b41593d995fbf2 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 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 warnings (new ones prefixed by >>): arch/s390/mm/vmem.c:520:6: warning: no previous prototype for 'vmemmap_free' [-Wmissing-prototypes] 520 | void vmemmap_free(unsigned long start, unsigned long end, | ^~~~~~~~~~~~ 535 | struct range arch_get_mappable_range(void) | ^~~~~~~~~~~~~~~~~~~~~~~ vim +/arch_get_mappable_range +535 arch/s390/mm/vmem.c 519 521 struct vmem_altmap *altmap) 522 { 523 mutex_lock(&vmem_mutex); 524 remove_pagetable(start, end, false); 525 mutex_unlock(&vmem_mutex); 526 } 527 528 void vmem_remove_mapping(unsigned long start, unsigned long size) 529 { 530 mutex_lock(&vmem_mutex); 531 vmem_remove_range(start, size); 532 mutex_unlock(&vmem_mutex); 533 } 534 536 { 537 struct range memhp_range; 538 539 memhp_range.start = 0; 540 memhp_range.end = VMEM_MAX_PHYS; 541 return memhp_range; 542 } 543 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org