Index: sys/arm64/xen/xen_arch_intr.c
===================================================================
--- sys/arm64/xen/xen_arch_intr.c
+++ sys/arm64/xen/xen_arch_intr.c
@@ -40,6 +40,7 @@
 #include <sys/pcpu.h>
 #include <sys/smp.h>
 #include <sys/syslog.h>
+#include <sys/intr.h>
 
 #include <xen/xen-os.h>
 #include <xen/arch-intr.h>
@@ -123,6 +124,20 @@
 		isrc = NULL;
 	}
 
+#ifdef SMP
+	if (type == EVTCHN_TYPE_PORT) {
+		static u_int current;
+
+		/*
+		 * By default all interrupts are assigned to vCPU#0
+		 * unless specified otherwise, so shuffle them to balance
+		 * the interrupt load.
+		 */
+		current = intr_irq_next_cpu(current, &all_cpus);
+		xen_intr_assign_cpu(isrc, current);
+	}
+#endif
+
 	return (isrc);
 }