Hi Marc, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: dea8dcf2a9fa8cc540136a6cd885c3beece16ec3 commit: 68b824e428c5fb5c3dc5ef80b1543e767534b58e KVM: arm64: Patch kimage_voffset instead of loading the EL1 value date: 5 weeks ago config: arm64-randconfig-r025-20201229 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project cee1e7d14f4628d6174b33640d502bff3b54ae45) 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 # install arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=68b824e428c5fb5c3dc5ef80b1543e767534b58e git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 68b824e428c5fb5c3dc5ef80b1543e767534b58e # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): arch/arm64/kvm/va_layout.c:138:6: warning: no previous prototype for function 'kvm_patch_vector_branch' [-Wmissing-prototypes] void kvm_patch_vector_branch(struct alt_instr *alt, ^ arch/arm64/kvm/va_layout.c:138:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void kvm_patch_vector_branch(struct alt_instr *alt, ^ static arch/arm64/kvm/va_layout.c:249:6: warning: no previous prototype for function 'kvm_update_kimg_phys_offset' [-Wmissing-prototypes] void kvm_update_kimg_phys_offset(struct alt_instr *alt, ^ arch/arm64/kvm/va_layout.c:249:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void kvm_update_kimg_phys_offset(struct alt_instr *alt, ^ static >> arch/arm64/kvm/va_layout.c:255:6: warning: no previous prototype for function 'kvm_get_kimage_voffset' [-Wmissing-prototypes] void kvm_get_kimage_voffset(struct alt_instr *alt, ^ arch/arm64/kvm/va_layout.c:255:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void kvm_get_kimage_voffset(struct alt_instr *alt, ^ static 3 warnings generated. vim +/kvm_get_kimage_voffset +255 arch/arm64/kvm/va_layout.c 254 > 255 void kvm_get_kimage_voffset(struct alt_instr *alt, --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org