diff --git a/sys/miscfs/specfs/spec_vnops.c b/sys/miscfs/specfs/spec_vnops.c
index 8f7cf00cf80e..e6a7891b0705 100644
--- a/sys/miscfs/specfs/spec_vnops.c
+++ b/sys/miscfs/specfs/spec_vnops.c
@@ -1672,6 +1672,7 @@ spec_close(void *v)
 		sd->sd_bdevvp = NULL;
 	}
 	if (count == 0) {
+		KASSERT(!sd->sd_closing);
 		sd->sd_opened = false;
 		sd->sd_closing = true;
 	}
@@ -1722,6 +1723,7 @@ spec_close(void *v)
 	 * reacquiring the lock would deadlock.
 	 */
 	mutex_enter(&device_lock);
+	KASSERT(!sd->sd_opened);
 	KASSERT(sd->sd_closing);
 	sd->sd_closing = false;
 	cv_broadcast(&specfs_iocv);