Re: [PATCH 5/5] LoongArch: Add pv ipi support on LoongArch system

[kernel test robot]

Hi Bibo,

kernel test robot noticed the following build warnings:

[auto build test WARNING on 610a9b8f49fbcf1100716370d3b5f6f884a2835a]

url:    https://github.com/intel-lab-lkp/linux/commits/Bibo-Mao/LoongArch-KVM-Add-hypercall-instruction-emulation-support/20240103-151946
base:   610a9b8f49fbcf1100716370d3b5f6f884a2835a
patch link:    https://lore.kernel.org/r/20240103071615.3422264-6-maobibo%40loongson.cn
patch subject: [PATCH 5/5] LoongArch: Add pv ipi support on LoongArch system
config: loongarch-randconfig-r061-20240109 (https://download.01.org/0day-ci/archive/20240109/202401091354.GtBERgQJ-lkp@xxxxxxxxx/config)
compiler: loongarch64-linux-gcc (GCC) 13.2.0

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202401091354.GtBERgQJ-lkp@xxxxxxxxx/

cocci warnings: (new ones prefixed by >>)
>> arch/loongarch/kvm/exit.c:681:5-8: Unneeded variable: "ret". Return "  0" on line 701
--
>> arch/loongarch/kvm/exit.c:720:2-3: Unneeded semicolon

vim +681 arch/loongarch/kvm/exit.c

   678	
   679	static int kvm_pv_send_ipi(struct kvm_vcpu *vcpu, int sgi)
   680	{
 > 681		int ret = 0;
   682		u64 ipi_bitmap;
   683		unsigned int min, cpu;
   684		struct kvm_vcpu *dest;
   685	
   686		ipi_bitmap = vcpu->arch.gprs[LOONGARCH_GPR_A1];
   687		min = vcpu->arch.gprs[LOONGARCH_GPR_A2];
   688	
   689		if (ipi_bitmap) {
   690			cpu = find_first_bit((void *)&ipi_bitmap, BITS_PER_LONG);
   691			while (cpu < BITS_PER_LONG) {
   692				if ((cpu + min) < KVM_MAX_VCPUS) {
   693					dest = kvm_get_vcpu_by_id(vcpu->kvm, cpu + min);
   694					kvm_queue_irq(dest, sgi);
   695					kvm_vcpu_kick(dest);
   696				}
   697				cpu = find_next_bit((void *)&ipi_bitmap, BITS_PER_LONG, cpu + 1);
   698			}
   699		}
   700	
 > 701		return ret;
   702	}
   703	
   704	/*
   705	 * hypcall emulation always return to guest, Caller should check retval.
   706	 */
   707	static void kvm_handle_pv_hcall(struct kvm_vcpu *vcpu)
   708	{
   709		unsigned long func = vcpu->arch.gprs[LOONGARCH_GPR_A0];
   710		long ret;
   711	
   712		switch (func) {
   713		case KVM_HC_FUNC_IPI:
   714			kvm_pv_send_ipi(vcpu, INT_SWI0);
   715			ret = KVM_HC_STATUS_SUCCESS;
   716			break;
   717		default:
   718			ret = KVM_HC_INVALID_CODE;
   719			break;
 > 720		};
   721	
   722		vcpu->arch.gprs[LOONGARCH_GPR_A0] = ret;
   723	}
   724	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki