tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 65f0d2414b7079556fbbcc070b3d1c9f9587606d commit: 7a2c094464e39a54f5b9228cd78208cd43872bbd arm64: entry: cleanup el0 svc handler naming date: 12 months ago config: arm64-randconfig-r005-20210113 (attached as .config) compiler: aarch64-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/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 7a2c094464e39a54f5b9228cd78208cd43872bbd # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm64 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/arm64/kernel/syscall.c:157:6: warning: no previous prototype for 'do_el0_svc' [-Wmissing-prototypes] 157 | void do_el0_svc(struct pt_regs *regs) | ^~~~~~~~~~ 164 | void do_el0_svc_compat(struct pt_regs *regs) | ^~~~~~~~~~~~~~~~~ vim +/do_el0_svc_compat +164 arch/arm64/kernel/syscall.c 162 163 #ifdef CONFIG_COMPAT --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org