*** old/src/share/vm/runtime/sweeper.cpp	Tue Oct  7 15:52:22 2014
--- new/src/share/vm/runtime/sweeper.cpp	Tue Oct  7 15:52:22 2014

*** 538,558 ****
--- 538,566 ----
      }
    } else if (nm->is_not_entrant()) {
      // If there are no current activations of this method on the
      // stack we can safely convert it to a zombie method
      if (nm->can_not_entrant_be_converted()) {
        if (PrintMethodFlushing && Verbose) {
          tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (not entrant) being made zombie", nm->compile_id(), nm);
        }
        // Clear ICStubs to prevent back patching stubs of zombie or unloaded
        // nmethods during the next safepoint (see ICStub::finalize).
+       {
          MutexLocker cl(CompiledIC_lock);
          nm->clear_ic_stubs();
+       }
+       // Acquiring the CompiledIC_lock may block for a safepoint and set the
+       // nmethod to zombie (see 'CodeCache::make_marked_nmethods_zombies').
+       // Check if nmethod is still non-entrant at this point.
+       if (nm->is_not_entrant()) {
+         if (PrintMethodFlushing && Verbose) {
+           tty->print_cr("### Nmethod %3d/" PTR_FORMAT " (not entrant) being made zombie", nm->compile_id(), nm);
+         }
          // Code cache state change is tracked in make_zombie()
          nm->make_zombie();
          _zombified_count++;
          SWEEP(nm);
+       }
+       assert(nm->is_zombie(), "nmethod must be zombie");
      } else {
        // Still alive, clean up its inline caches
        MutexLocker cl(CompiledIC_lock);
        nm->cleanup_inline_caches();
        SWEEP(nm);