diff --git a/openbsc/src/system_information.c b/openbsc/src/system_information.c
index df4f1a0..6493794 100644
--- a/openbsc/src/system_information.c
+++ b/openbsc/src/system_information.c
@@ -98,7 +98,7 @@
 static int bitvec2freq_list(u_int8_t *chan_list, struct bitvec *bv,
 			    const struct gsm_bts *bts)
 {
-	int i, rc, min = 1024, max = 0;
+	int i, rc, min = 1024, max = -1;
 
 	memset(chan_list, 0, 16);
 
@@ -128,6 +128,12 @@
 		}
 	}
 
+	if (max == -1) {
+		/* Empty set, use 'bit map 0 format' */
+		chan_list[0] = 0;
+		return 0;
+	}
+
 	if ((max - min) > 111) {
 		LOGP(DRR, LOGL_ERROR, "min_arfcn=%u, max_arfcn=%u, "
 			"distance > 111\n", min, max);