KVM: arm64: selftests: Add support for GICv2 on v3

The current vgic_init test wrongly assumes that the host cannot
multiple versions of the GIC architecture, while v2 emulation
on v3 has almost always been supported (it was supported before
the standalone v3 emulation).

Tweak the test to support multiple GIC incarnations.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Fixes: 3f4db37 ("KVM: arm64: selftests: Make vgic_init gic version agnostic")
Reviewed-by: Ricardo Koller <ricarkol@google.com>
Link: https://lore.kernel.org/r/20220714154108.3531213-1-maz@kernel.org

Author: Marc Zyngier

tools/testing/selftests/kvm/aarch64/vgic_init.c

@@ -670,7 +670,7 @@ int test_kvm_device(uint32_t gic_dev_type)
 
 	if (!_kvm_create_device(v.vm, other, true, &fd)) {
 		ret = _kvm_create_device(v.vm, other, false, &fd);
-		TEST_ASSERT(ret && errno == EINVAL,
+		TEST_ASSERT(ret && (errno == EINVAL || errno == EEXIST),
 				"create GIC device while other version exists");
 	}
 
@@ -698,6 +698,7 @@ int main(int ac, char **av)
 {
 	int ret;
 	int pa_bits;
+	int cnt_impl = 0;
 
 	pa_bits = vm_guest_mode_params[VM_MODE_DEFAULT].pa_bits;
 	max_phys_size = 1ULL << pa_bits;
@@ -706,17 +707,19 @@ int main(int ac, char **av)
 	if (!ret) {
 		pr_info("Running GIC_v3 tests.\n");
 		run_tests(KVM_DEV_TYPE_ARM_VGIC_V3);
-		return 0;
+		cnt_impl++;
 	}
 
 	ret = test_kvm_device(KVM_DEV_TYPE_ARM_VGIC_V2);
 	if (!ret) {
 		pr_info("Running GIC_v2 tests.\n");
 		run_tests(KVM_DEV_TYPE_ARM_VGIC_V2);
-		return 0;
+		cnt_impl++;
 	}
 
-	print_skip("No GICv2 nor GICv3 support");
-	exit(KSFT_SKIP);
+	if (!cnt_impl) {
+		print_skip("No GICv2 nor GICv3 support");
+		exit(KSFT_SKIP);
+	}
 	return 0;
 }