diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 9025a06..e492f5f 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -694,6 +694,12 @@
 		BUG();
 }
 
+static void event_handler_exit(struct irq_info *info)
+{
+	smp_store_release(&info->is_active, 0);
+	clear_evtchn(info->evtchn);
+}
+
 static void pirq_query_unmask(int irq)
 {
 	struct physdev_irq_status_query irq_status;
@@ -724,13 +730,13 @@
 	    likely(!irqd_irq_disabled(data))) {
 		do_mask(info, EVT_MASK_REASON_TEMPORARY);
 
-		clear_evtchn(evtchn);
+		event_handler_exit(info);
 
 		irq_move_masked_irq(data);
 
 		do_unmask(info, EVT_MASK_REASON_TEMPORARY);
 	} else
-		clear_evtchn(evtchn);
+		event_handler_exit(info);
 
 	if (pirq_needs_eoi(data->irq)) {
 		rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
@@ -1566,6 +1572,8 @@
 	}
 
 	info = info_for_irq(irq);
+	if (xchg_acquire(&info->is_active, 1))
+		return;
 
 	if (ctrl->defer_eoi) {
 		info->eoi_cpu = smp_processor_id();
@@ -1753,13 +1761,13 @@
 	    likely(!irqd_irq_disabled(data))) {
 		do_mask(info, EVT_MASK_REASON_TEMPORARY);
 
-		clear_evtchn(evtchn);
+		event_handler_exit(info);
 
 		irq_move_masked_irq(data);
 
 		do_unmask(info, EVT_MASK_REASON_TEMPORARY);
 	} else
-		clear_evtchn(evtchn);
+		event_handler_exit(info);
 }
 
 static void mask_ack_dynirq(struct irq_data *data)
@@ -1775,7 +1783,7 @@
 
 	if (VALID_EVTCHN(evtchn)) {
 		do_mask(info, EVT_MASK_REASON_EOI_PENDING);
-		clear_evtchn(evtchn);
+		event_handler_exit(info);
 	}
 }
 
@@ -1786,7 +1794,7 @@
 
 	if (VALID_EVTCHN(evtchn)) {
 		do_mask(info, EVT_MASK_REASON_EXPLICIT);
-		clear_evtchn(evtchn);
+		event_handler_exit(info);
 	}
 }
 
@@ -1895,10 +1903,11 @@
 /* Clear an irq's pending state, in preparation for polling on it */
 void xen_clear_irq_pending(int irq)
 {
-	int evtchn = evtchn_from_irq(irq);
+	struct irq_info *info = info_for_irq(irq);
+	evtchn_port_t evtchn = info ? info->evtchn : 0;
 
 	if (VALID_EVTCHN(evtchn))
-		clear_evtchn(evtchn);
+		event_handler_exit(info);
 }
 EXPORT_SYMBOL(xen_clear_irq_pending);
 void xen_set_irq_pending(int irq)
diff --git a/drivers/xen/events/events_internal.h b/drivers/xen/events/events_internal.h
index dd3748e..d3a89b4 100644
--- a/drivers/xen/events/events_internal.h
+++ b/drivers/xen/events/events_internal.h
@@ -38,6 +38,7 @@
 #define EVT_MASK_REASON_EXPLICIT	0x01
 #define EVT_MASK_REASON_TEMPORARY	0x02
 #define EVT_MASK_REASON_EOI_PENDING	0x04
+	u8 is_active;		/* Is event just being handled? */
 	unsigned irq;
 	unsigned int evtchn;	/* event channel */
 	unsigned short cpu;	/* cpu bound */