tree: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.19.y head: e864f43593ccf9180c61738abdf1c1dde091367d commit: 86834898d5a5e5aef9ae6d285201f2d99a4eb300 [7414/9999] mm/memory_hotplug: shrink zones when offlining memory config: ia64-randconfig-r031-20210318 (attached as .config) compiler: ia64-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://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.gi... git remote add linux-stable-rc https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git git fetch --no-tags linux-stable-rc linux-4.19.y git checkout 86834898d5a5e5aef9ae6d285201f2d99a4eb300 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=ia64 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 >>): In file included from arch/ia64/include/asm/pgtable.h:154, from include/linux/memremap.h:7, from include/linux/mm.h:27, from mm/memory_hotplug.c:8: arch/ia64/include/asm/mmu_context.h: In function 'reload_context': arch/ia64/include/asm/mmu_context.h:137:41: warning: variable 'old_rr4' set but not used [-Wunused-but-set-variable] 137 | unsigned long rr0, rr1, rr2, rr3, rr4, old_rr4; | ^~~~~~~ mm/memory_hotplug.c: In function '__remove_section': 482 | unsigned long start_pfn; | ^~~~~~~~~ Kconfig warnings: (for reference only) WARNING: unmet direct dependencies detected for FRAME_POINTER Depends on DEBUG_KERNEL && (M68K || UML || SUPERH) || ARCH_WANT_FRAME_POINTERS Selected by - FAULT_INJECTION_STACKTRACE_FILTER && FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT && !X86_64 && !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC && !X86 vim +/start_pfn +482 mm/memory_hotplug.c 815121d2b5cd56 Yasuaki Ishimatsu 2013-02-22 478 86834898d5a5e5 David Hildenbrand 2020-01-28 479 static void __remove_section(struct mem_section *ms, unsigned long map_offset, efaa8fb877a081 David Hildenbrand 2020-01-28 480 struct vmem_altmap *altmap) ea01ea937dcae2 Badari Pulavarty 2008-04-28 481 { 815121d2b5cd56 Yasuaki Ishimatsu 2013-02-22 @482 unsigned long start_pfn; 815121d2b5cd56 Yasuaki Ishimatsu 2013-02-22 483 int scn_nr; ea01ea937dcae2 Badari Pulavarty 2008-04-28 484 efaa8fb877a081 David Hildenbrand 2020-01-28 485 if (WARN_ON_ONCE(!valid_section(ms))) efaa8fb877a081 David Hildenbrand 2020-01-28 486 return; ea01ea937dcae2 Badari Pulavarty 2008-04-28 487 815121d2b5cd56 Yasuaki Ishimatsu 2013-02-22 488 scn_nr = __section_nr(ms); 1dd2bfc86818dd YASUAKI ISHIMATSU 2017-10-03 489 start_pfn = section_nr_to_pfn((unsigned long)scn_nr); 815121d2b5cd56 Yasuaki Ishimatsu 2013-02-22 490 dc6be8597c8c29 David Hildenbrand 2020-01-28 491 sparse_remove_one_section(ms, map_offset, altmap); ea01ea937dcae2 Badari Pulavarty 2008-04-28 492 } ea01ea937dcae2 Badari Pulavarty 2008-04-28 493 :::::: The code at line 482 was first introduced by commit :::::: 815121d2b5cd56f1757d4468dc3abadd06a0ed6b memory_hotplug: clear zone when removing the memory :::::: TO: Yasuaki Ishimatsu <isimatu.yasuaki(a)jp.fujitsu.com&gt; :::::: CC: Linus Torvalds <torvalds(a)linux-foundation.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org