--- a/src/share/vm/runtime/thread.cpp	Sat Sep 03 14:03:54 2011 -0700
+++ b/src/share/vm/runtime/thread.cpp	Mon Sep 05 17:09:05 2011 -0700
@@ -2859,6 +2859,44 @@
   }
 }
 
+class PrintAndVerifyOopClosure: public OopClosure {
+ protected:
+  template <class T> inline void do_oop_work(T* p) {
+    oop obj = oopDesc::load_decode_heap_oop(p);
+    if (obj == NULL) return;
+    tty->print(INTPTR_FORMAT ": ", p);
+    if (obj->is_oop_or_null()) {
+      if (obj->is_objArray()) {
+        tty->print_cr("valid objArray: " INTPTR_FORMAT, (oopDesc*) obj);
+      } else {
+        obj->print();
+      }
+    } else {
+      tty->print_cr("invalid oop: " INTPTR_FORMAT, (oopDesc*) obj);
+    }
+    tty->cr();
+  }
+ public:
+  virtual void do_oop(oop* p) { do_oop_work(p); }
+  virtual void do_oop(narrowOop* p)  { do_oop_work(p); }
+};
+
+
+static void oops_print(frame* f, const RegisterMap *map) {
+  PrintAndVerifyOopClosure print;
+  f->print_value();
+  f->oops_do(&print, NULL, (RegisterMap*)map);
+}
+
+// Print our all the locations that contain oops and whether they are
+// valid or not.  This useful when trying to find the oldest frame
+// where an oop has gone bad since the frame walk is from youngest to
+// oldest.
+void JavaThread::trace_oops() {
+  tty->print_cr("[Trace oops]");
+  frames_do(oops_print);
+}
+
 
 #ifdef ASSERT
 // Print or validate the layout of stack frames