--- /var/current/src/sys/cam/scsi/scsi_pass.c	2008-11-22 16:58:50.000000000 +0800
+++ /usr/src/sys/cam/scsi/scsi_pass.c	2008-12-21 12:59:36.000000000 +0800
@@ -347,8 +347,10 @@
 	if ((softc->flags & PASS_FLAG_OPEN) == 0) {
 		softc->flags |= PASS_FLAG_OPEN;
 	} else {
-		/* Device closes aren't symmertical, so fix up the refcount */
+		/* Device closes aren't symmetrical, so fix up the refcount */
+		cam_periph_unlock(periph);
 		cam_periph_release(periph);
+		return(EINVAL);
 	}
 
 	cam_periph_unlock(periph);