--- a/arch/x86/kvm/xen.c
+++ x/arch/x86/kvm/xen.c
@@ -165,6 +165,8 @@ static void kvm_xen_stop_timer(struct kv
 
 static void kvm_xen_init_timer(struct kvm_vcpu *vcpu)
 {
+	if (vcpu->arch.xen.timer.function == xen_timer_callback)
+		return;
 	hrtimer_init(&vcpu->arch.xen.timer, CLOCK_MONOTONIC,
 		     HRTIMER_MODE_ABS_HARD);
 	vcpu->arch.xen.timer.function = xen_timer_callback;