Index: sys/kern/kern_timeout.c
===================================================================
--- sys/kern/kern_timeout.c	(revisione 234720)
+++ sys/kern/kern_timeout.c	(copia locale)
@@ -906,8 +906,19 @@ again:
 		 * callout, then we can't stop it, so just bail.
 		 */
 		if (cc->cc_curr != c) {
-			CTR3(KTR_CALLOUT, "failed to stop %p func %p arg %p",
-			    c, c->c_func, c->c_arg);
+
+			/*
+			 * Make sure to cancel any pending migration.
+			 */
+			if (cc_cme_migrating(cc)) {
+				cc_cme_cleanup(cc);
+				CTR3(KTR_CALLOUT,
+			"cancelled deferred migration for %p func %p arg %p",
+				    c, c->c_func, c->c_arg);
+			} else
+				CTR3(KTR_CALLOUT,
+				    "failed to stop %p func %p arg %p",
+				    c, c->c_func, c->c_arg);
 			CC_UNLOCK(cc);
 			if (sq_locked)
 				sleepq_release(&cc->cc_waiting);