diff --git a/sys/dev/iscsi/iscsi.c b/sys/dev/iscsi/iscsi.c
index 242d033452e..a0ae2427390 100644
--- a/sys/dev/iscsi/iscsi.c
+++ b/sys/dev/iscsi/iscsi.c
@@ -1766,15 +1766,17 @@ iscsi_ioctl_session_add(struct iscsi_softc *sc, struct iscsi_session_add *isa)
 	arc4rand(&is->is_isid[1], 5, 0);
 	is->is_tsih = 0;
 	callout_init(&is->is_callout, 1);
-	callout_reset(&is->is_callout, 1 * hz, iscsi_callout, is);
-	TAILQ_INSERT_TAIL(&sc->sc_sessions, is, is_next);
 
 	error = kthread_add(iscsi_maintenance_thread, is, NULL, NULL, 0, 0, "iscsimt");
 	if (error != 0) {
 		ISCSI_SESSION_WARN(is, "kthread_add(9) failed with error %d", error);
+		sx_xunlock(&sc->sc_lock);
 		return (error);
 	}
 
+	callout_reset(&is->is_callout, 1 * hz, iscsi_callout, is);
+	TAILQ_INSERT_TAIL(&sc->sc_sessions, is, is_next);
+
 	/*
 	 * Trigger immediate reconnection.
 	 */