diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
index 610beba35907..22c08af97013 100644
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -713,7 +713,9 @@ int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
 				break;
 			}
 			vcpu->arch.xen.timer_virq = data->u.timer.port;
-			kvm_xen_init_timer(vcpu);
+
+			if (!vcpu->arch.xen.timer.function)
+				kvm_xen_init_timer(vcpu);
 
 			/* Restart the timer if it's set */
 			if (data->u.timer.expires_ns)