--- old/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	2014-05-20 13:35:45.599988092 +0200
+++ new/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	2014-05-20 13:35:45.450553392 +0200
@@ -2173,12 +2173,6 @@
 }
 
 void G1CollectedHeap::stop() {
-#if 0
-  // Stopping concurrent worker threads is currently disabled until
-  // some bugs in concurrent mark has been resolve. Without fixing
-  // those bugs first we risk haning during VM exit when trying to
-  // stop these threads.
-
   // 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)
@@ -2186,7 +2180,6 @@
   _cm->root_regions()->abort();
   _cm->root_regions()->wait_until_scan_finished();
   stop_conc_gc_threads();
-#endif
 }
 
 size_t G1CollectedHeap::conservative_max_heap_alignment() {