KVM: arm/arm64: vgic: Check return value for kvm_register_vgic_device

kvm_register_device_ops() can return an error, so lets check its return
value and propagate this up the call chain.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index 0130c4b..2f24f13 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -210,20 +210,24 @@
 	kfree(dev);
 }
 
-void kvm_register_vgic_device(unsigned long type)
+int kvm_register_vgic_device(unsigned long type)
 {
+	int ret = -ENODEV;
+
 	switch (type) {
 	case KVM_DEV_TYPE_ARM_VGIC_V2:
-		kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
-					KVM_DEV_TYPE_ARM_VGIC_V2);
+		ret = kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
+					      KVM_DEV_TYPE_ARM_VGIC_V2);
 		break;
 #ifdef CONFIG_KVM_ARM_VGIC_V3
 	case KVM_DEV_TYPE_ARM_VGIC_V3:
-		kvm_register_device_ops(&kvm_arm_vgic_v3_ops,
-					KVM_DEV_TYPE_ARM_VGIC_V3);
+		ret = kvm_register_device_ops(&kvm_arm_vgic_v3_ops,
+					      KVM_DEV_TYPE_ARM_VGIC_V3);
 		break;
 #endif
 	}
+
+	return ret;
 }
 
 /** vgic_attr_regs_access: allows user space to read/write VGIC registers
@@ -428,4 +432,3 @@
 };
 
 #endif /* CONFIG_KVM_ARM_VGIC_V3 */
-