diff --git a/src/platform/tests/test-common.c b/src/platform/tests/test-common.c
index d3bb78a906..2838e5f03d 100644
--- a/src/platform/tests/test-common.c
+++ b/src/platform/tests/test-common.c
@@ -1980,6 +1980,23 @@ nmtstp_link_set_updown (NMPlatform *platform,
 
 /*****************************************************************************/
 
+gboolean
+nmtstp_kernel_support_get (NMPlatformKernelSupportType type)
+{
+	NMTernary v;
+
+	v = nm_platform_kernel_support_get_full (type, FALSE);
+	if (v != NM_TERNARY_DEFAULT)
+		return v != NM_TERNARY_FALSE;
+
+	switch (type) {
+	default:
+		g_assert_not_reached ();
+	}
+}
+
+/*****************************************************************************/
+
 struct _NMTstpNamespaceHandle {
 	pid_t pid;
 	int pipe_fd;
diff --git a/src/platform/tests/test-common.h b/src/platform/tests/test-common.h
index 050ea23e8f..0a01e99a90 100644
--- a/src/platform/tests/test-common.h
+++ b/src/platform/tests/test-common.h
@@ -318,6 +318,8 @@ gboolean nmtstp_platform_ip6_route_delete (NMPlatform *platform, int ifindex, st
 const NMPlatformLink *nmtstp_link_get_typed (NMPlatform *platform, int ifindex, const char *name, NMLinkType link_type);
 const NMPlatformLink *nmtstp_link_get (NMPlatform *platform, int ifindex, const char *name);
 
+gboolean nmtstp_kernel_support_get (NMPlatformKernelSupportType type);
+
 void nmtstp_link_set_updown (NMPlatform *platform,
                              gboolean external_command,
                              int ifindex,