Hi Jinyang, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 2b14864acbaaf03d9c01982e243a84632524c3ac commit: a307a4ce9ecd2e23c71318201330d9d648b3f818 MIPS: Loongson64: Add KASLR support date: 1 year, 1 month ago config: mips-randconfig-r012-20211216 (https://download.01.org/0day-ci/archive/20211216/202112161913.eRJj41Fh-lk...) compiler: mips64el-linux-gcc (GCC) 11.2.0 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/torvalds/linux.git/commit... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout a307a4ce9ecd2e23c71318201330d9d648b3f818 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=mips SHELL=/bin/bash arch/mips/kernel/ arch/mips/lib/ 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 >>): 41 | int __weak plat_post_relocation(long offset) | ^~~~~~~~~~~~~~~~~~~~ arch/mips/kernel/relocate.c:135:12: warning: no previous prototype for 'do_relocations' [-Wmissing-prototypes] 135 | int __init do_relocations(void *kbase_old, void *kbase_new, long offset) | ^~~~~~~~~~~~~~ 304 | void *__init relocate_kernel(void) | ^~~~~~~~~~~~~~~ arch/mips/kernel/relocate.c:415:6: warning: no previous prototype for 'show_kernel_relocation' [-Wmissing-prototypes] 415 | void show_kernel_relocation(const char *level) | ^~~~~~~~~~~~~~~~~~~~~~ vim +/plat_post_relocation +41 arch/mips/kernel/relocate.c 4c9fff362261d68 Marcin Nowakowski 2016-11-23 35 8cc709d7d4f013f Steven J. Hill 2016-12-09 36 /* 8cc709d7d4f013f Steven J. Hill 2016-12-09 37 * This function may be defined for a platform to perform any post-relocation 8cc709d7d4f013f Steven J. Hill 2016-12-09 38 * fixup necessary. 8cc709d7d4f013f Steven J. Hill 2016-12-09 39 * Return non-zero to abort relocation 8cc709d7d4f013f Steven J. Hill 2016-12-09 40 */ 8cc709d7d4f013f Steven J. Hill 2016-12-09 @41 int __weak plat_post_relocation(long offset) 8cc709d7d4f013f Steven J. Hill 2016-12-09 42 { 8cc709d7d4f013f Steven J. Hill 2016-12-09 43 return 0; 8cc709d7d4f013f Steven J. Hill 2016-12-09 44 } 8cc709d7d4f013f Steven J. Hill 2016-12-09 45 :::::: The code at line 41 was first introduced by commit :::::: 8cc709d7d4f013f51d38ceb2e3c8c82d230cf457 MIPS: Relocatable: Provide plat_post_relocation hook :::::: TO: Steven J. Hill <Steven.Hill(a)cavium.com&gt; :::::: CC: Ralf Baechle <ralf(a)linux-mips.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org