diff --git a/sys/kern/kern_intr.c b/sys/kern/kern_intr.c
--- a/sys/kern/kern_intr.c
+++ b/sys/kern/kern_intr.c
@@ -527,11 +527,10 @@
 }
 
 int
-intr_event_destroy(struct intr_event *ie)
+intr_event_destroy_(struct intr_event *ie)
 {
 
-	if (ie == NULL)
-		return (EINVAL);
+	MPASS(ie != NULL);
 
 	mtx_lock(&event_lock);
 	mtx_lock(&ie->ie_lock);
@@ -550,6 +549,16 @@
 	return (0);
 }
 
+int
+intr_event_destroy(struct intr_event *ie)
+{
+
+	if (ie == NULL)
+		return (EINVAL);
+
+	return (intr_event_destroy_(ie));
+}
+
 static struct intr_thread *
 ithread_create(const char *name)
 {
@@ -1342,7 +1351,7 @@
  * o EINVAL:                    stray interrupt.
  */
 int
-intr_event_handle(struct intr_event *ie, struct trapframe *frame)
+intr_event_handle_(struct intr_event *ie, struct trapframe *frame)
 {
 	struct intr_handler *ih;
 	struct trapframe *oldframe;
@@ -1357,8 +1366,10 @@
 	intr_prof_stack_use(td, frame);
 #endif
 
-	/* An interrupt with no event or handlers is a stray interrupt. */
-	if (ie == NULL || CK_SLIST_EMPTY(&ie->ie_handlers))
+	MPASS(ie != NULL);
+
+	/* An interrupt with no handlers is a stray interrupt. */
+	if (CK_SLIST_EMPTY(&ie->ie_handlers))
 		return (EINVAL);
 
 	/*
@@ -1459,6 +1470,17 @@
 	return (0);
 }
 
+int
+intr_event_handle(struct intr_event *ie, struct trapframe *frame)
+{
+
+        /* An interrupt with no event is a stray interrupt. */
+        if (ie == NULL)
+                return (EINVAL);
+
+	return (intr_event_handle_(ie, frame));
+}
+
 #ifdef DDB
 /*
  * Dump details about an interrupt handler
diff --git a/sys/kern/subr_intr.c b/sys/kern/subr_intr.c
--- a/sys/kern/subr_intr.c
+++ b/sys/kern/subr_intr.c
@@ -405,7 +405,7 @@
 	} else
 #endif
 	if (isrc->isrc_event != NULL) {
-		if (intr_event_handle(isrc->isrc_event, tf) == 0)
+		if (intr_event_handle_(isrc->isrc_event, tf) == 0)
 			return (0);
 	}
 
diff --git a/sys/sys/interrupt.h b/sys/sys/interrupt.h
--- a/sys/sys/interrupt.h
+++ b/sys/sys/interrupt.h
@@ -182,7 +182,9 @@
 	    __printflike(9, 10);
 int	intr_event_describe_handler(struct intr_event *ie, void *cookie,
 	    const char *descr);
+int	intr_event_destroy_(struct intr_event *ie) __result_use_check;
 int	intr_event_destroy(struct intr_event *ie);
+int	intr_event_handle_(struct intr_event *ie, struct trapframe *frame);
 int	intr_event_handle(struct intr_event *ie, struct trapframe *frame);
 int	intr_event_remove_handler(void *cookie);
 int	intr_event_suspend_handler(void *cookie);
diff --git a/sys/x86/x86/intr_machdep.c b/sys/x86/x86/intr_machdep.c
--- a/sys/x86/x86/intr_machdep.c
+++ b/sys/x86/x86/intr_machdep.c
@@ -321,6 +321,8 @@
 	struct intr_event *ie;
 	int vector;
 
+	MPASS(isrc != NULL);
+
 	/*
 	 * We count software interrupts when we process them.  The
 	 * code here follows previous practice, but there's an
@@ -332,6 +334,8 @@
 
 	ie = isrc->is_event;
 
+	MPASS(ie != NULL);
+
 	/*
 	 * XXX: We assume that IRQ 0 is only used for the ISA timer
 	 * device (clk).
@@ -344,7 +348,7 @@
 	 * For stray interrupts, mask and EOI the source, bump the
 	 * stray count, and log the condition.
 	 */
-	if (intr_event_handle(ie, frame) != 0) {
+	if (intr_event_handle_(ie, frame) != 0) {
 		isrc->is_pic->pic_disable_source(isrc, PIC_EOI);
 		(*isrc->is_straycount)++;
 		if (*isrc->is_straycount < INTR_STRAY_LOG_MAX)