From 6767c6547b4b6174ad16d3714700ea33e51a0977 Mon Sep 17 00:00:00 2001
From: Jeff Roberson <jeff@FreeBSD.org>
Date: Sun, 1 Feb 2004 01:24:54 +0000
Subject: [PATCH]  - Assert that td_critnest > 0 in critical_exit() to catch
 cases of    unbalanced uses of the critical_* api.

---
 sys/kern/kern_switch.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sys/kern/kern_switch.c b/sys/kern/kern_switch.c
index ee38e88d9fcd..a8ead79984d7 100644
--- a/sys/kern/kern_switch.c
+++ b/sys/kern/kern_switch.c
@@ -443,6 +443,8 @@ critical_exit(void)
 {
 	struct thread *td;
 
+	KASSERT(td->td_critnest > 0,
+	    ("critical_exit:  critnest < 0"));
 	td = curthread;
 	if (td->td_critnest == 1) {
 		td->td_critnest = 0;