Hi Marc,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on kvmarm/next]
[also build test WARNING on next-20201210]
[cannot apply to arm64/for-next/core soc/for-next arm/for-next xlnx/master linus/master kvm/linux-next v5.10-rc7]
[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/Marc-Zyngier/KVM-arm64-ARMv8-3-8-4-Nested-Virtualization-support/20201211-004741
base:   https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git next
config: arm64-defconfig (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://github.com/0day-ci/linux/commit/af7a3cada1fa577612a86dd0a7c4016ffed68acc
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Marc-Zyngier/KVM-arm64-ARMv8-3-8-4-Nested-Virtualization-support/20201211-004741
        git checkout af7a3cada1fa577612a86dd0a7c4016ffed68acc
        # 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/arch_timer.c: In function 'kvm_timer_vcpu_load_nested_switch':
>> arch/arm64/kvm/arch_timer.c:656:10: warning: variable 'ret' set but not used [-Wunused-but-set-variable]
     656 |  int hw, ret;
         |          ^~~

vim +/ret +656 arch/arm64/kvm/arch_timer.c

   652	
   653	static void kvm_timer_vcpu_load_nested_switch(struct kvm_vcpu *vcpu,
   654						      struct timer_map *map)
   655	{
 > 656		int hw, ret;
   657	
   658		if (!irqchip_in_kernel(vcpu->kvm))
   659			return;
   660	
   661		/*
   662		 * We only ever unmap the vtimer irq on a VHE system that runs nested
   663		 * virtualization, in which case we have both a valid emul_vtimer,
   664		 * emul_ptimer, direct_vtimer, and direct_ptimer.
   665		 *
   666		 * Since this is called from kvm_timer_vcpu_load(), a change between
   667		 * vEL2 and vEL1/0 will have just happened, and the timer_map will
   668		 * represent this, and therefore we switch the emul/direct mappings
   669		 * below.
   670		 */
   671		hw = kvm_vgic_get_map(vcpu, map->direct_vtimer->irq.irq);
   672		if (hw < 0) {
   673			kvm_vgic_unmap_phys_irq(vcpu, map->emul_vtimer->irq.irq);
   674			kvm_vgic_unmap_phys_irq(vcpu, map->emul_ptimer->irq.irq);
   675	
   676			ret = kvm_vgic_map_phys_irq(vcpu,
   677						    map->direct_vtimer->host_timer_irq,
   678						    map->direct_vtimer->irq.irq,
   679						    kvm_arch_timer_get_input_level);
   680			ret = kvm_vgic_map_phys_irq(vcpu,
   681						    map->direct_ptimer->host_timer_irq,
   682						    map->direct_ptimer->irq.irq,
   683						    kvm_arch_timer_get_input_level);
   684		}
   685	}
   686	

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