Hi Vivek, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on kvm/linux-next] [also build test WARNING on linux/master linus/master v5.8-rc4 next-20200707] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Vivek-Goyal/kvm-x86-Exit-to-user... base: https://git.kernel.org/pub/scm/virt/kvm/kvm.git linux-next config: x86_64-allyesconfig (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 02946de3802d3bc65bc9f2eb9b8d4969b5a7add8) 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 x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 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 >>): bool kvm_find_error_gfn(struct kvm_vcpu *vcpu, gfn_t gfn) ^ arch/x86/kvm/x86.c:10403:1: note: declare 'static' if the function is not intended to be used outside of this translation unit bool kvm_find_error_gfn(struct kvm_vcpu *vcpu, gfn_t gfn) ^ static 1 warning generated. vim +/kvm_find_error_gfn +10403 arch/x86/kvm/x86.c 10402 10403 bool kvm_find_error_gfn(struct kvm_vcpu *vcpu, gfn_t gfn) 10404 { 10405 u32 key = kvm_error_gfn_hash_fn(gfn); 10406 10407 return vcpu->arch.apf.error_gfns[key] == gfn; 10408 } 10409 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org