diff --git a/openbsc/src/gsm_04_11.c b/openbsc/src/gsm_04_11.c
index 8db402b..9218783 100644
--- a/openbsc/src/gsm_04_11.c
+++ b/openbsc/src/gsm_04_11.c
@@ -162,19 +162,11 @@
 	u_int8_t address_lv[12]; /* according to 03.40 / 9.1.2.5 */
 	int rc = 0;
 
-	if (!tall_sms_ctx)
-		tall_sms_ctx = talloc_named_const(tall_bsc_ctx, 1,
-						  "sms_submit");
-
 	sms = talloc(tall_sms_ctx, struct sms_submit);
 	if (!sms)
 		return -ENOMEM;
 	memset(sms, 0, sizeof(*sms));
 
-	if (!tall_gsms_ctx)
-		tall_gsms_ctx = talloc_named_const(tall_bsc_ctx, 1,
-						   "sms");
-
 	gsms = talloc(tall_gsms_ctx, struct gsm_sms);
 	if (!gsms) {
 		talloc_free(sms);
@@ -513,3 +505,9 @@
 
 	return gsm0411_sendmsg(msg);
 }
+
+static __attribute__((constructor)) void on_dso_load_sms(void)
+{
+	tall_sms_ctx = talloc_named_const(tall_bsc_ctx, 1, "sms_submit");
+	tall_gsms_ctx = talloc_named_const(tall_bsc_ctx, 1, "sms");
+}