--- old/src/share/vm/oops/method.cpp	2016-10-07 14:39:34.376786453 +0200
+++ new/src/share/vm/oops/method.cpp	2016-10-07 14:39:34.300786456 +0200
@@ -97,7 +97,10 @@
   // Fix and bury in Method*
   set_interpreter_entry(NULL); // sets i2i entry and from_int
   set_adapter_entry(NULL);
-  clear_code(); // from_c/from_i get set to c2i/i2i
+  {
+    MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
+    clear_code(); // from_c/from_i get set to c2i/i2i
+  }
 
   if (access_flags.is_native()) {
     clear_native_function();
@@ -781,6 +784,7 @@
   set_native_function(
     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
     !native_bind_event_is_interesting);
+  MutexLockerEx pl(Patching_lock, Mutex::_no_safepoint_check_flag);
   clear_code();
 }
 
@@ -905,7 +909,7 @@
 
 // Revert to using the interpreter and clear out the nmethod
 void Method::clear_code() {
-
+  assert_locked_or_safepoint(Patching_lock);
   // this may be NULL if c2i adapters have not been made yet
   // Only should happen at allocate time.
   if (adapter() == NULL) {
@@ -1074,6 +1078,7 @@
 
 // Install compiled code.  Instantly it can execute.
 void Method::set_code(methodHandle mh, CompiledMethod *code) {
+  assert_locked_or_safepoint(Patching_lock);
   assert( code, "use clear_code to remove code" );
   assert( mh->check_code(), "" );