--- a/usr/src/uts/common/os/clock.c	Tue Apr 27 11:44:30 2010 -0400
+++ b/usr/src/uts/common/os/clock.c	Tue Apr 27 09:48:22 2010 -0700
@@ -2590,7 +2590,8 @@
 			/*
 			 * Switching from cyclic to event driven mode.
 			 */
-			if (atomic_cas_32(&lb_info->lbi_token, 0, 1) == 0) {
+			if (panicstr == NULL &&
+			    atomic_cas_32(&lb_info->lbi_token, 0, 1) == 0) {
 
 				if (lbolt_hybrid == lbolt_event_driven) {
 					ret = atomic_dec_32_nv(

--- a/usr/src/uts/common/os/panic.c	Tue Apr 27 11:44:30 2010 -0400
+++ b/usr/src/uts/common/os/panic.c	Tue Apr 27 09:48:22 2010 -0700
@@ -19,8 +19,7 @@
  * CDDL HEADER END
  */
 /*
- * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
- * Use is subject to license terms.
+ * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
  */
 
 /*
@@ -222,11 +221,6 @@
 	t->t_bound_cpu = cp;
 	t->t_preempt++;
 
-	/*
-	 * Switch lbolt to event driven mode.
-	 */
-	lbolt_hybrid = lbolt_event_driven;
-
 	panic_enter_hw(s);
 
 	/*