--- a/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	Thu May 22 09:12:29 2014 +0200
+++ b/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	Fri Apr 11 11:00:12 2014 +0200
@@ -435,6 +435,9 @@
 void G1CollectedHeap::stop_conc_gc_threads() {
   _cg1r->stop();
   _cmThread->stop();
+  if (G1StringDedup::is_enabled()) {
+    G1StringDedup::stop();
+  }
 }
 
 #ifdef ASSERT
@@ -2182,6 +2185,16 @@
   return JNI_OK;
 }
 
+void G1CollectedHeap::stop() {
+  // Abort any ongoing concurrent root region scanning and stop all
+  // concurrent threads. We do this to make sure these threads do
+  // not continue to execute and access resources (e.g. gclog_or_tty)
+  // that are destroyed during shutdown.
+  _cm->root_regions()->abort();
+  _cm->root_regions()->wait_until_scan_finished();
+  stop_conc_gc_threads();
+}
+
 size_t G1CollectedHeap::conservative_max_heap_alignment() {
   return HeapRegion::max_region_size();
 }