Index: sys/dev/ioat/ioat.c
===================================================================
--- sys/dev/ioat/ioat.c
+++ sys/dev/ioat/ioat.c
@@ -220,8 +220,6 @@
 		goto err;
 
 	ioat->version = ioat_read_cbver(ioat);
-	ioat_interrupt_setup(ioat);
-
 	if (ioat->version < IOAT_VER_3_0) {
 		error = ENODEV;
 		goto err;
@@ -407,6 +405,10 @@
 	ioat_write_chancmp(ioat, ioat->comp_update_bus_addr);
 	ioat_write_chainaddr(ioat, ring[0]->hw_desc_bus_addr);
 
+	error = ioat_interrupt_setup(ioat);
+	if (error != 0)
+		return (error);
+
 	error = ioat3_selftest(ioat);
 	if (error != 0)
 		return (error);
Index: sys/dev/ioat/ioat_hw.h
===================================================================
--- sys/dev/ioat/ioat_hw.h
+++ sys/dev/ioat/ioat_hw.h
@@ -39,6 +39,7 @@
 
 #define	IOAT_INTRCTRL_OFFSET		0x03
 #define	IOAT_INTRCTRL_MASTER_INT_EN	0x01
+#define	IOAT_INTRCTRL_MSIX_VECTOR_CONTROL	0x08
 
 #define	IOAT_ATTNSTATUS_OFFSET		0x04