--- old/src/cpu/x86/vm/sharedRuntime_x86_64.cpp	2015-10-14 13:53:39.684724526 +0200
+++ new/src/cpu/x86/vm/sharedRuntime_x86_64.cpp	2015-10-14 13:53:39.578727089 +0200
@@ -2447,6 +2447,7 @@
     // Load the oop from the handle
     __ movptr(obj_reg, Address(oop_handle_reg, 0));
 
+    oopDesc::bs()->interpreter_write_barrier(masm, obj_reg);
     if (UseBiasedLocking) {
       __ biased_locking_enter(lock_reg, obj_reg, swap_reg, rscratch1, false, lock_done, &slow_path_lock);
     }
@@ -2615,6 +2616,7 @@
 
     // Get locked oop from the handle we passed to jni
     __ movptr(obj_reg, Address(oop_handle_reg, 0));
+    oopDesc::bs()->interpreter_write_barrier(masm, obj_reg);
 
     Label done;