tree: https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git kvm/mm-hacking head: e5759e0ca29728e31bd3fd0137ec905eecb15bf9 commit: a77ba8a5f9ded36915ebab3e8bb3c75430c9ad92 [20/22] BACKPORT: KVM: arm64: Shadow table for KVM EL2 state config: arm64-randconfig-r035-20211019 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project d245f2e8597bfb52c34810a328d42b990e4af1a4) 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/will/linux.git/commit/?id... git remote add arm-perf https://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git git fetch --no-tags arm-perf kvm/mm-hacking git checkout a77ba8a5f9ded36915ebab3e8bb3c75430c9ad92 # 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 <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): void put_shadow_vcpu(struct kvm_vcpu *vcpu, int exit_code) ^ arch/arm64/kvm/hyp/nvhe/hyp-main.c:40:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void put_shadow_vcpu(struct kvm_vcpu *vcpu, int exit_code) ^ static arch/arm64/kvm/hyp/nvhe/hyp-main.c:292:6: warning: no previous prototype for function 'handle_trap' [-Wmissing-prototypes] void handle_trap(struct kvm_cpu_context *host_ctxt) ^ arch/arm64/kvm/hyp/nvhe/hyp-main.c:292:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void handle_trap(struct kvm_cpu_context *host_ctxt) ^ static 2 warnings generated. -- void clear_shadow_cache(void) ^ arch/arm64/kvm/hyp/nvhe/pkvm.c:90:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void clear_shadow_cache(void) ^ static arch/arm64/kvm/hyp/nvhe/pkvm.c:329:8: error: implicit declaration of function 'check_host_memory_addr' [-Werror,-Wimplicit-function-declaration] ret = check_host_memory_addr((u64)kvm, sizeof(*kvm)); ^ arch/arm64/kvm/hyp/nvhe/pkvm.c:404:15: error: implicit declaration of function 'check_host_memory_addr' [-Werror,-Wimplicit-function-declaration] if (unlikely(check_host_memory_addr((u64)kvm, sizeof(*kvm)))) ^ arch/arm64/kvm/hyp/nvhe/pkvm.c:399:14: warning: unused variable 'shadow_kvm_pa' [-Wunused-variable] phys_addr_t shadow_kvm_pa; ^ 2 warnings and 2 errors generated. vim +/put_shadow_vcpu +40 arch/arm64/kvm/hyp/nvhe/hyp-main.c 39 41 { 42 } 43 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org