v4.19.13 snapshot.
diff --git a/tools/lib/lockdep/lockdep.c b/tools/lib/lockdep/lockdep.c
new file mode 100644
index 0000000..6002fcf
--- /dev/null
+++ b/tools/lib/lockdep/lockdep.c
@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/lockdep.h>
+#include <stdlib.h>
+
+/* Trivial API wrappers, we don't (yet) have RCU in user-space: */
+#define hlist_for_each_entry_rcu	hlist_for_each_entry
+#define hlist_add_head_rcu		hlist_add_head
+#define hlist_del_rcu			hlist_del
+#define list_for_each_entry_rcu		list_for_each_entry
+#define list_add_tail_rcu		list_add_tail
+
+u32 prandom_u32(void)
+{
+	/* Used only by lock_pin_lock() which is dead code */
+	abort();
+}
+
+static struct new_utsname *init_utsname(void)
+{
+	static struct new_utsname n = (struct new_utsname) {
+		.release = "liblockdep",
+		.version = LIBLOCKDEP_VERSION,
+	};
+
+	return &n;
+}
+
+#include "../../../kernel/locking/lockdep.c"