Index: head/sys/dev/hyperv/vmbus/hv_hv.c
===================================================================
--- head/sys/dev/hyperv/vmbus/hv_hv.c
+++ head/sys/dev/hyperv/vmbus/hv_hv.c
@@ -46,6 +46,7 @@
 #include <dev/hyperv/include/hyperv_busdma.h>
 #include <dev/hyperv/vmbus/hv_vmbus_priv.h>
 #include <dev/hyperv/vmbus/hyperv_reg.h>
+#include <dev/hyperv/vmbus/vmbus_var.h>
 
 #define HV_NANOSECONDS_PER_SEC		1000000000L
 
@@ -220,8 +221,8 @@
  */
 void
 hv_vmbus_synic_init(void *arg)
-
 {
+	struct vmbus_softc *sc = vmbus_get_softc();
 	int			cpu;
 	uint64_t		hv_vcpu_index;
 	hv_vmbus_synic_simp	simp;
@@ -266,7 +267,7 @@
 
 	/*HV_SHARED_SINT_IDT_VECTOR + 0x20; */
 	shared_sint.as_uint64_t = 0;
-	shared_sint.u.vector = setup_args->vector;
+	shared_sint.u.vector = sc->vmbus_idtvec;
 	shared_sint.u.masked = FALSE;
 	shared_sint.u.auto_eoi = TRUE;
 
Index: head/sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c
===================================================================
--- head/sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c
+++ head/sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c
@@ -385,25 +385,18 @@
 	sc = vmbus_get_softc();
 
 	/*
-	 * Find a free IDT slot for vmbus callback.
+	 * Find a free IDT vector for vmbus messages/events.
 	 */
-	hv_vmbus_g_context.hv_cb_vector = lapic_ipi_alloc(IDTVEC(hv_vmbus_callback));
-	if (hv_vmbus_g_context.hv_cb_vector < 0) {
-		if(bootverbose)
-			printf("Error VMBUS: Cannot find free IDT slot for "
-			    "vmbus callback!\n");
+	sc->vmbus_idtvec = lapic_ipi_alloc(IDTVEC(hv_vmbus_callback));
+	if (sc->vmbus_idtvec < 0) {
+		device_printf(sc->vmbus_dev, "cannot find free IDT vector\n");
 		ret = ENXIO;
 		goto cleanup;
 	}
-
-	if(bootverbose)
-		printf("VMBUS: vmbus callback vector %d\n",
-		    hv_vmbus_g_context.hv_cb_vector);
-
-	/*
-	 * Notify the hypervisor of our vector.
-	 */
-	setup_args.vector = hv_vmbus_g_context.hv_cb_vector;
+	if(bootverbose) {
+		device_printf(sc->vmbus_dev, "vmbus IDT vector %d\n",
+		    sc->vmbus_idtvec);
+	}
 
 	CPU_FOREACH(j) {
 		snprintf(buf, sizeof(buf), "cpu%d:hyperv", j);
@@ -493,7 +486,7 @@
 		}
 	}
 
-	lapic_ipi_free(hv_vmbus_g_context.hv_cb_vector);
+	lapic_ipi_free(sc->vmbus_idtvec);
 
 	cleanup:
 	return (ret);
@@ -553,6 +546,7 @@
 static int
 vmbus_detach(device_t dev)
 {
+	struct vmbus_softc *sc = device_get_softc(dev);
 	int i;
 
 	hv_vmbus_release_unattached_channels();
@@ -573,7 +567,7 @@
 		}
 	}
 
-	lapic_ipi_free(hv_vmbus_g_context.hv_cb_vector);
+	lapic_ipi_free(sc->vmbus_idtvec);
 
 	return (0);
 }
Index: head/sys/dev/hyperv/vmbus/hv_vmbus_priv.h
===================================================================
--- head/sys/dev/hyperv/vmbus/hv_vmbus_priv.h
+++ head/sys/dev/hyperv/vmbus/hv_vmbus_priv.h
@@ -216,11 +216,6 @@
 	struct taskqueue		*hv_event_queue[MAXCPU];
 	struct taskqueue		*hv_msg_tq[MAXCPU];
 	struct task			hv_msg_task[MAXCPU];
-	/*
-	 * Host use this vector to interrupt guest for vmbus channel
-	 * event and msg.
-	 */
-	int				hv_cb_vector;
 } hv_vmbus_context;
 
 /*
@@ -763,7 +758,6 @@
 void			vmbus_scan(void);
 
 typedef struct {
-	unsigned int	vector;
 	void		*page_buffers[2 * MAXCPU];
 } hv_setup_args;
 
Index: head/sys/dev/hyperv/vmbus/vmbus_var.h
===================================================================
--- head/sys/dev/hyperv/vmbus/vmbus_var.h
+++ head/sys/dev/hyperv/vmbus/vmbus_var.h
@@ -39,6 +39,7 @@
 	void			(*vmbus_event_proc)(struct vmbus_softc *, int);
 	struct vmbus_pcpu_data	vmbus_pcpu[MAXCPU];
 	device_t		vmbus_dev;
+	int			vmbus_idtvec;
 };
 
 extern struct vmbus_softc	*vmbus_sc;