tree: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf/core head: a9f4a6e92b3b319296fb078da2615f618f6cd80c commit: e1bfc24577cc65c95dc519d7621a9c985b97e567 [12/17] KVM: Move x86's perf guest info callbacks to generic KVM config: arm64-buildonly-randconfig-r004-20211122 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project c133fb321f7ca6083ce15b6aa5bf89de6600e649) 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/tip/tip.git/commit/?id=e1bfc24577cc65c95dc519d7621a9c985b97e567 git remote add tip https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git git fetch --no-tags tip perf/core git checkout e1bfc24577cc65c95dc519d7621a9c985b97e567 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 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/arm.c:499:15: warning: no previous prototype for function 'kvm_arch_vcpu_get_ip' [-Wmissing-prototypes] unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) ^ arch/arm64/kvm/arm.c:499:1: note: declare 'static' if the function is not intended to be used outside of this translation unit unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) ^ static 1 warning generated. vim +/kvm_arch_vcpu_get_ip +499 arch/arm64/kvm/arm.c 498 > 499 unsigned long kvm_arch_vcpu_get_ip(struct kvm_vcpu *vcpu) 500 { 501 return *vcpu_pc(vcpu); 502 } 503 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org