Hi Geert, I love your patch! Yet something to improve: [auto build test ERROR on robh/for-next] [also build test ERROR on arm64/for-next/core arm/for-next linus/master v5.14-rc5 next-20210811] [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/Geert-Uytterhoeven/Add-generic-s... base: https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next config: ia64-allmodconfig (attached as .config) compiler: ia64-linux-gcc (GCC) 10.3.0 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/34ef57fdde286c4999f0deea8ee16d56d... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Geert-Uytterhoeven/Add-generic-support-for-kdump-DT-properties/20210811-165455 git checkout 34ef57fdde286c4999f0deea8ee16d56d2ac3bae # save the attached .config to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross O=build_dir ARCH=ia64 SHELL=/bin/bash drivers/ 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 >>): 593 | static void __init reserve_elfcorehdr(void) | ^~~~~~~~~~~~~~~~~~ In file included from arch/ia64/include/asm/mmzone.h:16, from arch/ia64/include/asm/nodedata.h:17, from arch/ia64/include/asm/processor.h:81, from arch/ia64/include/asm/thread_info.h:12, from include/linux/thread_info.h:60, from include/asm-generic/preempt.h:5, from ./arch/ia64/include/generated/asm/preempt.h:1, from include/linux/preempt.h:78, from include/linux/rcupdate.h:27, from include/linux/rculist.h:11, from include/linux/pid.h:5, from include/linux/sched.h:14, from include/linux/ptrace.h:6, from arch/ia64/include/asm/user.h:32, from include/linux/user.h:1, from include/linux/elfcore.h:5, from include/linux/crash_core.h:6, from include/linux/kexec.h:18, from include/linux/crash_dump.h:5, from drivers/of/fdt.c:11: arch/ia64/include/asm/meminit.h:43:12: note: previous declaration of 'reserve_elfcorehdr' was here 43 | extern int reserve_elfcorehdr(u64 *start, u64 *end); | ^~~~~~~~~~~~~~~~~~ vim +/reserve_elfcorehdr +593 drivers/of/fdt.c 584 585 /* 586 * reserve_elfcorehdr() - reserves memory for elf core header 587 * 588 * This function reserves the memory occupied by an elf core header 589 * described in the device tree. This region contains all the 590 * information about primary kernel's core image and is used by a dump 591 * capture kernel to access the system memory on primary kernel. 592 */ 594 { 595 if (!IS_ENABLED(CONFIG_CRASH_DUMP) || !elfcorehdr_size) 596 return; 597 598 if (memblock_is_region_reserved(elfcorehdr_addr, elfcorehdr_size)) { 599 pr_warn("elfcorehdr is overlapped\n"); 600 return; 601 } 602 603 memblock_reserve(elfcorehdr_addr, elfcorehdr_size); 604 605 pr_info("Reserving %llu KiB of memory at 0x%llx for elfcorehdr\n", 606 elfcorehdr_size >> 10, elfcorehdr_addr); 607 } 608 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org