Hi Gavin, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on kvm/queue] [also build test WARNING on kvmarm/next linus/master v6.0-rc5 next-20220916] [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#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Gavin-Shan/KVM-arm64-Enable-ring-based-dirty-memory-tracking/20220916-125417 base: https://git.kernel.org/pub/scm/virt/kvm/kvm.git queue config: arm64-allyesconfig (https://download.01.org/0day-ci/archive/20220918/202209180726.FLL69aKA-lkp@xxxxxxxxx/config) compiler: aarch64-linux-gcc (GCC) 12.1.0 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/intel-lab-lkp/linux/commit/a1a4cd8f6a5e8927f800baff7d965870a1b7d7ba git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Gavin-Shan/KVM-arm64-Enable-ring-based-dirty-memory-tracking/20220916-125417 git checkout a1a4cd8f6a5e8927f800baff7d965870a1b7d7ba # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> arch/arm64/kvm/../../../virt/kvm/dirty_ring.c:14:12: warning: no previous prototype for 'kvm_cpu_dirty_log_size' [-Wmissing-prototypes] 14 | int __weak kvm_cpu_dirty_log_size(void) | ^~~~~~~~~~~~~~~~~~~~~~ vim +/kvm_cpu_dirty_log_size +14 arch/arm64/kvm/../../../virt/kvm/dirty_ring.c fb04a1eddb1a65 Peter Xu 2020-09-30 13 fb04a1eddb1a65 Peter Xu 2020-09-30 @14 int __weak kvm_cpu_dirty_log_size(void) fb04a1eddb1a65 Peter Xu 2020-09-30 15 { fb04a1eddb1a65 Peter Xu 2020-09-30 16 return 0; fb04a1eddb1a65 Peter Xu 2020-09-30 17 } fb04a1eddb1a65 Peter Xu 2020-09-30 18 -- 0-DAY CI Kernel Test Service https://01.org/lkp