Index: sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c
===================================================================
--- sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c
+++ sys/dev/hyperv/vmbus/hv_vmbus_drv_freebsd.c
@@ -382,8 +382,12 @@
 #ifdef HYPERV
 extern inthand_t IDTVEC(rsvd), IDTVEC(hv_vmbus_callback);
 
+#define VMBUS_IDT_START	IDT_DTRACE_RET 
+#define VMBUS_IDT_END	APIC_TIMER_INT
+
 /**
  * @brief Find a free IDT slot and setup the interrupt handler.
+ * range: (VMBUS_IDT_START, VMBUS_IDT_END)
  */
 static int
 vmbus_vector_alloc(void)
@@ -397,8 +401,8 @@
 	 * as vmbus channel callback vector. We install 'hv_vmbus_callback'
 	 * handler at that vector and use it to interrupt vcpus.
 	 */
-	vector = APIC_SPURIOUS_INT;
-	while (--vector >= APIC_IPI_INTS) {
+	vector = VMBUS_IDT_END;
+	while (--vector > VMBUS_IDT_START) {
 		ip = &idt[vector];
 		func = ((long)ip->gd_hioffset << 16 | ip->gd_looffset);
 		if (func == (uintptr_t)&IDTVEC(rsvd)) {
@@ -428,7 +432,7 @@
 	if (vector == 0)
 		return;
 
-        KASSERT(vector >= APIC_IPI_INTS && vector < APIC_SPURIOUS_INT,
+        KASSERT(vector > VMBUS_IDT_START && vector < VMBUS_IDT_END,
             ("invalid vector %d", vector));
 
         ip = &idt[vector];