diff --git a/sys/kern/kern_mutex.c b/sys/kern/kern_mutex.c
index f06813a3321d..81addbe1a640 100644
--- a/sys/kern/kern_mutex.c
+++ b/sys/kern/kern_mutex.c
@@ -883,10 +883,6 @@ mtx_destroy(struct mtx *m)
 	else {
 		MPASS((m->mtx_lock & (MTX_RECURSED|MTX_CONTESTED)) == 0);
 
-		/* Perform the non-mtx related part of mtx_unlock_spin(). */
-		if (LO_CLASSINDEX(&m->mtx_object) == LOCK_CLASS_SPIN_MUTEX)
-			spinlock_exit();
-
 		/* Tell witness this isn't locked to make it happy. */
 		WITNESS_UNLOCK(&m->mtx_object, LOP_EXCLUSIVE, __FILE__,
 		    __LINE__);