diff --git a/src/gb/gprs_ns.c b/src/gb/gprs_ns.c
index cee4885..c77ebb3 100644
--- a/src/gb/gprs_ns.c
+++ b/src/gb/gprs_ns.c
@@ -1552,7 +1552,7 @@
 
 const char *gprs_ns_ll_str(const struct gprs_nsvc *nsvc)
 {
-	static char buf[80];
+	static __thread char buf[80];
 	return gprs_ns_ll_str_buf(buf, sizeof(buf), nsvc);
 }