diff --git a/hw/i386/kvm/xen_evtchn.c b/hw/i386/kvm/xen_evtchn.c
index dd566c4967..173e0818c7 100644
--- a/hw/i386/kvm/xen_evtchn.c
+++ b/hw/i386/kvm/xen_evtchn.c
@@ -1877,7 +1877,7 @@ int xen_physdev_map_pirq(struct physdev_map_pirq *map)
             return pirq;
         }
         map->pirq = pirq;
-    } else if (pirq > s->nr_pirqs) {
+    } else if (pirq >= s->nr_pirqs) {
         return -EINVAL;
     } else {
         /*