diff --git a/sys/cddl/compat/opensolaris/sys/mutex.h b/sys/cddl/compat/opensolaris/sys/mutex.h
index b1982e7245b0..9875901242e0 100644
--- a/sys/cddl/compat/opensolaris/sys/mutex.h
+++ b/sys/cddl/compat/opensolaris/sys/mutex.h
@@ -47,9 +47,9 @@ typedef enum {
 typedef struct sx	kmutex_t;
 
 #ifndef OPENSOLARIS_WITNESS
-#define	MUTEX_FLAGS	(SX_DUPOK | SX_NOWITNESS)
+#define	MUTEX_FLAGS	(SX_DUPOK | SX_NEW | SX_NOWITNESS)
 #else
-#define	MUTEX_FLAGS	(SX_DUPOK)
+#define	MUTEX_FLAGS	(SX_DUPOK | SX_NEW)
 #endif
 
 #define	mutex_init(lock, desc, type, arg)	do {			\
@@ -57,7 +57,6 @@ typedef struct sx	kmutex_t;
 	ASSERT((type) == 0 || (type) == MUTEX_DEFAULT);			\
 	KASSERT(((lock)->lock_object.lo_flags & LO_ALLMASK) !=		\
 	    LO_EXPECTED, ("lock %s already initialized", #lock));	\
-	bzero((lock), sizeof(struct sx));				\
 	for (_name = #lock; *_name != '\0'; _name++) {			\
 		if (*_name >= 'a' && *_name <= 'z')			\
 			break;						\