--- a/hotspot/src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp	Fri Jun 28 18:28:17 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.cpp	Sun Jun 30 21:42:07 2013 +0200
@@ -47,7 +47,7 @@
     JavaThread* jt = (JavaThread*)thr;
     jt->satb_mark_queue().enqueue(pre_val);
   } else {
-    MutexLocker x(Shared_SATB_Q_lock);
+    MutexLockerEx x(Shared_SATB_Q_lock, Mutex::_no_safepoint_check_flag);
     JavaThread::satb_mark_queue_set().shared_satb_queue()->enqueue(pre_val);
   }
 }