Hi David,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on dennis-percpu/for-next]
[also build test WARNING on linus/master v5.10-rc3 next-20201109]
[cannot apply to kvmarm/next arm64/for-next/core soc/for-next arm/for-next xlnx/master]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/David-Brazdil/Opt-in-always-on-nVHE-hypervisor/20201109-193833
base:   https://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu.git for-next
config: arm64-randconfig-r022-20201109 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 09ec07827b1128504457a93dee80b2ceee1af600)
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://github.com/0day-ci/linux/commit/a59ab708ed6039e83756720b1d5974e84db5a8f4
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review David-Brazdil/Opt-in-always-on-nVHE-hypervisor/20201109-193833
        git checkout a59ab708ed6039e83756720b1d5974e84db5a8f4
        # 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 <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> arch/arm64/kvm/arm.c:1875:13: warning: no previous prototype for function 'kvm_patch_hcr_flags' [-Wmissing-prototypes]
   void __init kvm_patch_hcr_flags(struct alt_instr *alt,
               ^
   arch/arm64/kvm/arm.c:1875:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void __init kvm_patch_hcr_flags(struct alt_instr *alt,
   ^
   static 
   1 warning generated.

vim +/kvm_patch_hcr_flags +1875 arch/arm64/kvm/arm.c

  1874	
> 1875	void __init kvm_patch_hcr_flags(struct alt_instr *alt,
  1876					__le32 *origptr, __le32 *updptr, int nr_inst)
  1877	{
  1878		int i;
  1879		u32 rd;
  1880	
  1881		BUG_ON(nr_inst != 4);
  1882	
  1883		/* Skip for VHE and unprotected nVHE modes. */
  1884		if (!is_kvm_protected_mode())
  1885			return;
  1886	
  1887		rd = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RD,
  1888						  le32_to_cpu(origptr[0]));
  1889	
  1890		for (i = 0; i < nr_inst; i++) {
  1891			u32 oinsn = __gen_mov_hcr_insn(HCR_HOST_NVHE_FLAGS, rd, i);
  1892			u32 insn = __gen_mov_hcr_insn(HCR_HOST_NVHE_PROTECTED_FLAGS, rd, i);
  1893	
  1894			BUG_ON(oinsn != le32_to_cpu(origptr[i]));
  1895			updptr[i] = cpu_to_le32(insn);
  1896		}
  1897	}
  1898	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org