diff --git a/src/mds/SimpleLock.h b/src/mds/SimpleLock.h
index 725c4488c17f0a..ef41c408855712 100644
--- a/src/mds/SimpleLock.h
+++ b/src/mds/SimpleLock.h
@@ -417,6 +417,7 @@ class SimpleLock {
     ceph_assert(state == LOCK_XLOCK || state == LOCK_XLOCKDONE ||
 	   state == LOCK_XLOCKSNAP || state == LOCK_LOCK_XLOCK ||
 	   state == LOCK_LOCK  || /* if we are a leader of a peer */
+	   state == LOCK_PREXLOCK ||
 	   is_locallock());
     --more()->num_xlock;
     parent->put(MDSCacheObject::PIN_LOCK);