Hi David,

FYI, the error/warning still remains.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   dbe69e43372212527abf48609aba7fc39a6daa27
commit: cdf367192766ad11a03e8d5098556be43b8eb6b0 KVM: arm64: Intercept host's CPU_ON SMCs
date:   7 months ago
config: arm64-buildonly-randconfig-r002-20210701 (attached as .config)
compiler: aarch64-linux-gcc (GCC) 9.3.0
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
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cdf367192766ad11a03e8d5098556be43b8eb6b0
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout cdf367192766ad11a03e8d5098556be43b8eb6b0
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 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/hyp/nvhe/psci-relay.c:174:28: warning: no previous prototype for 'kvm_host_psci_cpu_entry' [-Wmissing-prototypes]
     174 | asmlinkage void __noreturn kvm_host_psci_cpu_entry(bool is_cpu_on)
         |                            ^~~~~~~~~~~~~~~~~~~~~~~


vim +/kvm_host_psci_cpu_entry +174 arch/arm64/kvm/hyp/nvhe/psci-relay.c

   173	
 > 174	asmlinkage void __noreturn kvm_host_psci_cpu_entry(bool is_cpu_on)
   175	{
   176		struct psci_boot_args *boot_args;
   177		struct kvm_cpu_context *host_ctxt;
   178	
   179		host_ctxt = &this_cpu_ptr(hyp_symbol_addr(kvm_host_data))->host_ctxt;
   180		boot_args = this_cpu_ptr(hyp_symbol_addr(cpu_on_args));
   181	
   182		cpu_reg(host_ctxt, 0) = boot_args->r0;
   183		write_sysreg_el2(boot_args->pc, SYS_ELR);
   184		release_boot_args(boot_args);
   185	
   186		__host_enter(host_ctxt);
   187	}
   188	

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