tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: aab7ee9f8ff0110bfcd594b33dc33748dc1baf46 commit: c34b26b98caca48ec9ee981d4a89ac4f73376a3a [6264/9127] KVM: MIPS: clean up redundant 'kvm_run' parameters config: mips-randconfig-r005-20200719 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project ed6b578040a85977026c93bf4188f996148f3218) 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 mips cross compiling tool for clang build # apt-get install binutils-mips-linux-gnu git checkout c34b26b98caca48ec9ee981d4a89ac4f73376a3a # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): arch/mips/kvm/emulate.c:946:23: warning: no previous prototype for function 'kvm_mips_emul_eret' [-Wmissing-prototypes] enum emulation_result kvm_mips_emul_eret(struct kvm_vcpu *vcpu) ^ arch/mips/kvm/emulate.c:946:1: note: declare 'static' if the function is not intended to be used outside of this translation unit enum emulation_result kvm_mips_emul_eret(struct kvm_vcpu *vcpu) ^ static arch/mips/kvm/emulate.c:1029:23: warning: no previous prototype for function 'kvm_mips_emul_tlbr' [-Wmissing-prototypes] enum emulation_result kvm_mips_emul_tlbr(struct kvm_vcpu *vcpu) ^ arch/mips/kvm/emulate.c:1029:1: note: declare 'static' if the function is not intended to be used outside of this translation unit enum emulation_result kvm_mips_emul_tlbr(struct kvm_vcpu *vcpu) ^ static arch/mips/kvm/emulate.c:1102:23: warning: no previous prototype for function 'kvm_mips_emul_tlbwi' [-Wmissing-prototypes] enum emulation_result kvm_mips_emul_tlbwi(struct kvm_vcpu *vcpu) ^ arch/mips/kvm/emulate.c:1102:1: note: declare 'static' if the function is not intended to be used outside of this translation unit enum emulation_result kvm_mips_emul_tlbwi(struct kvm_vcpu *vcpu) ^ static arch/mips/kvm/emulate.c:1138:23: warning: no previous prototype for function 'kvm_mips_emul_tlbwr' [-Wmissing-prototypes] enum emulation_result kvm_mips_emul_tlbwr(struct kvm_vcpu *vcpu) ^ arch/mips/kvm/emulate.c:1138:1: note: declare 'static' if the function is not intended to be used outside of this translation unit enum emulation_result kvm_mips_emul_tlbwr(struct kvm_vcpu *vcpu) ^ static arch/mips/kvm/emulate.c:1163:23: warning: no previous prototype for function 'kvm_mips_emul_tlbp' [-Wmissing-prototypes] enum emulation_result kvm_mips_emul_tlbp(struct kvm_vcpu *vcpu) ^ arch/mips/kvm/emulate.c:1163:1: note: declare 'static' if the function is not intended to be used outside of this translation unit enum emulation_result kvm_mips_emul_tlbp(struct kvm_vcpu *vcpu) ^ static arch/mips/kvm/emulate.c:1733:28: warning: shift count >= width of type [-Wshift-count-overflow] ((vcpu->arch.gprs[rt] >> 56) & 0xff); ^ ~~ arch/mips/kvm/emulate.c:1737:28: warning: shift count >= width of type [-Wshift-count-overflow] ((vcpu->arch.gprs[rt] >> 48) & 0xffff); ^ ~~ arch/mips/kvm/emulate.c:1741:28: warning: shift count >= width of type [-Wshift-count-overflow] ((vcpu->arch.gprs[rt] >> 40) & 0xffffff); ^ ~~ arch/mips/kvm/emulate.c:1745:28: warning: shift count >= width of type [-Wshift-count-overflow] ((vcpu->arch.gprs[rt] >> 32) & 0xffffffff); ^ ~~ arch/mips/kvm/emulate.c:1795:27: warning: shift count >= width of type [-Wshift-count-overflow] (vcpu->arch.gprs[rt] << 32); ^ ~~ arch/mips/kvm/emulate.c:1799:27: warning: shift count >= width of type [-Wshift-count-overflow] (vcpu->arch.gprs[rt] << 40); ^ ~~ arch/mips/kvm/emulate.c:1803:27: warning: shift count >= width of type [-Wshift-count-overflow] (vcpu->arch.gprs[rt] << 48); ^ ~~ arch/mips/kvm/emulate.c:1807:27: warning: shift count >= width of type [-Wshift-count-overflow] (vcpu->arch.gprs[rt] << 56); ^ ~~ kvm_mips_complete_mmio_load(vcpu, run); ~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^~~ arch/mips/include/asm/kvm_host.h:1072:30: note: 'kvm_mips_complete_mmio_load' declared here extern enum emulation_result kvm_mips_complete_mmio_load(struct kvm_vcpu *vcpu); ^ 13 warnings and 1 error generated. vim +/vcpu +2126 arch/mips/kvm/emulate.c dc6d95b153e78e arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2111 e685c689f3a84e arch/mips/kvm/kvm_mips_emul.c Sanjay Lal 2012-11-21 2112 default: d86c1ebe8e3d8a arch/mips/kvm/emulate.c James Hogan 2016-06-14 2113 kvm_err("Load not yet supported (inst=0x%08x)\n", 258f3a2ea93ff7 arch/mips/kvm/emulate.c James Hogan 2016-06-15 2114 inst.word); 8b48d5b75dc4cb arch/mips/kvm/emulate.c James Hogan 2017-03-14 2115 vcpu->mmio_needed = 0; 8b48d5b75dc4cb arch/mips/kvm/emulate.c James Hogan 2017-03-14 2116 return EMULATE_FAIL; e685c689f3a84e arch/mips/kvm/kvm_mips_emul.c Sanjay Lal 2012-11-21 2117 } e685c689f3a84e arch/mips/kvm/kvm_mips_emul.c Sanjay Lal 2012-11-21 2118 8b48d5b75dc4cb arch/mips/kvm/emulate.c James Hogan 2017-03-14 2119 run->mmio.is_write = 0; 8b48d5b75dc4cb arch/mips/kvm/emulate.c James Hogan 2017-03-14 2120 vcpu->mmio_is_write = 0; f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2121 f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2122 r = kvm_io_bus_read(vcpu, KVM_MMIO_BUS, f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2123 run->mmio.phys_addr, run->mmio.len, run->mmio.data); f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2124 f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2125 if (!r) { f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 @2126 kvm_mips_complete_mmio_load(vcpu, run); f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2127 vcpu->mmio_needed = 0; f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2128 return EMULATE_DONE; f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2129 } f21db3090de2c0 arch/mips/kvm/emulate.c Huacai Chen 2020-05-23 2130 8b48d5b75dc4cb arch/mips/kvm/emulate.c James Hogan 2017-03-14 2131 return EMULATE_DO_MMIO; e685c689f3a84e arch/mips/kvm/kvm_mips_emul.c Sanjay Lal 2012-11-21 2132 } e685c689f3a84e arch/mips/kvm/kvm_mips_emul.c Sanjay Lal 2012-11-21 2133 :::::: The code at line 2126 was first introduced by commit :::::: f21db3090de2c056728dee76d5fb66343aaf6dd1 KVM: MIPS: Add Loongson-3 Virtual IPI interrupt support :::::: TO: Huacai Chen <chenhc(a)lemote.com&gt; :::::: CC: Paolo Bonzini <pbonzini(a)redhat.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org