--- old/src/share/vm/gc/g1/g1CollectedHeap.cpp	2016-05-09 21:13:14.123390177 +0900
+++ new/src/share/vm/gc/g1/g1CollectedHeap.cpp	2016-05-09 21:13:13.919890873 +0900
@@ -2641,6 +2641,8 @@
 }
 
 void G1CollectedHeap::print_on(outputStream* st) const {
+  assert_locked_or_safepoint(Heap_lock);
+
   st->print(" %-20s", "garbage-first heap");
   st->print(" total " SIZE_FORMAT "K, used " SIZE_FORMAT "K",
             capacity()/K, used_unlocked()/K);
--- old/src/share/vm/gc/parallel/parallelScavengeHeap.cpp	2016-05-09 21:13:15.249052993 +0900
+++ new/src/share/vm/gc/parallel/parallelScavengeHeap.cpp	2016-05-09 21:13:15.040053708 +0900
@@ -551,6 +551,8 @@
 }
 
 void ParallelScavengeHeap::print_on(outputStream* st) const {
+  assert_locked_or_safepoint(Heap_lock);
+
   young_gen()->print_on(st);
   old_gen()->print_on(st);
   MetaspaceAux::print_on(st);
--- old/src/share/vm/gc/shared/genCollectedHeap.cpp	2016-05-09 21:13:15.934717315 +0900
+++ new/src/share/vm/gc/shared/genCollectedHeap.cpp	2016-05-09 21:13:15.793551131 +0900
@@ -1089,6 +1089,8 @@
 }
 
 void GenCollectedHeap::print_on(outputStream* st) const {
+  assert_locked_or_safepoint(Heap_lock);
+
   _young_gen->print_on(st);
   _old_gen->print_on(st);
   MetaspaceAux::print_on(st);
--- old/src/share/vm/memory/universe.cpp	2016-05-09 21:13:16.601131702 +0900
+++ new/src/share/vm/memory/universe.cpp	2016-05-09 21:13:16.443465575 +0900
@@ -1071,13 +1071,13 @@
 }
 
 void Universe::print_on(outputStream* st) {
+  GCMutexLocker hl(Heap_lock); // Heap_lock might be locked by caller thread.
   st->print_cr("Heap");
   heap()->print_on(st);
 }
 
 void Universe::print_heap_at_SIGBREAK() {
   if (PrintHeapAtSIGBREAK) {
-    MutexLocker hl(Heap_lock);
     print_on(tty);
     tty->cr();
     tty->flush();
--- old/src/share/vm/services/diagnosticCommand.cpp	2016-05-09 21:13:17.760153788 +0900
+++ new/src/share/vm/services/diagnosticCommand.cpp	2016-05-09 21:13:17.143796513 +0900
@@ -413,6 +413,7 @@
 }
 
 void HeapInfoDCmd::execute(DCmdSource source, TRAPS) {
+  MutexLocker hl(Heap_lock);
   Universe::heap()->print_on(output());
 }
 
--- old/src/share/vm/utilities/vmError.cpp	2016-05-09 21:13:18.470568025 +0900
+++ new/src/share/vm/utilities/vmError.cpp	2016-05-09 21:13:18.287235318 +0900
@@ -731,6 +731,7 @@
   STEP("printing heap information")
 
      if (_verbose && Universe::is_fully_initialized()) {
+       MutexLockerEx hl(Heap_lock, true); // No safepoint check
        Universe::heap()->print_on_error(st);
        st->cr();
        st->print_cr("Polling page: " INTPTR_FORMAT, p2i(os::get_polling_page()));
@@ -907,6 +908,7 @@
   // STEP("printing heap information")
 
   if (Universe::is_fully_initialized()) {
+    MutexLocker hl(Heap_lock);
     Universe::heap()->print_on_error(st);
     st->cr();
     st->print_cr("Polling page: " INTPTR_FORMAT, p2i(os::get_polling_page()));