diff --git a/ChangeLog b/ChangeLog
index 152c6406b6..c2ccbcc0f6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Dec 27 15:08:27 2014  Eric Wong  <e@80x24.org>
+
+	* vm_core.h (rb_vm_living_threads_insert): preserve order
+	  [Bug #10660] [ruby-core:67154] [ruby-core:67159]
+
 Sat Dec 27 13:08:20 2014  SHIBATA Hiroshi  <shibata.hiroshi@gmail.com>
 
 	* ext/socket/socket.c: improved document for YARD doc.
diff --git a/vm_core.h b/vm_core.h
index 93163098e2..809da4e86f 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -975,7 +975,7 @@ rb_vm_living_threads_init(rb_vm_t *vm)
 static inline void
 rb_vm_living_threads_insert(rb_vm_t *vm, rb_thread_t *th)
 {
-    list_add(&vm->living_threads, &th->vmlt_node);
+    list_add_tail(&vm->living_threads, &th->vmlt_node);
     vm->living_thread_num++;
 }