diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index d439afef9212..94c963462d74 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2159,12 +2159,13 @@ static void gsm_error(struct gsm_mux *gsm,
 static void gsm_cleanup_mux(struct gsm_mux *gsm, bool disc)
 {
 	int i;
-	struct gsm_dlci *dlci = gsm->dlci[0];
+	struct gsm_dlci *dlci;
 	struct gsm_msg *txq, *ntxq;
 
 	gsm->dead = true;
 	mutex_lock(&gsm->mutex);
 
+	dlci = gsm->dlci[0];
 	if (dlci) {
 		if (disc && dlci->state != DLCI_CLOSED) {
 			gsm_dlci_begin_close(dlci);