8245877: assert(_value != __null) failed: resolving NULL _value in JvmtiExport::post_compiled_method_load

Reviewed-by: sspitsyn, dholmes, coleenp

src/hotspot/share/code/nmethod.cpp

@@ -1608,6 +1608,8 @@ void nmethod::post_compiled_method_load_event(JvmtiThreadState* state) {
     if (is_not_entrant() && can_convert_to_zombie()) {
       return;
     }
+    // Ensure the sweeper can't collect this nmethod until it become "active" with JvmtiThreadState::nmethods_do.
+    mark_as_seen_on_stack();
   }
 
   // This is a bad time for a safepoint.  We don't want

src/hotspot/share/prims/jvmtiExport.cpp

@@ -2206,6 +2206,7 @@ void JvmtiExport::post_compiled_method_load(JvmtiEnv* env, nmethod *nm) {
   ResourceMark rm(thread);
   HandleMark hm(thread);
 
+  assert(!nm->is_zombie(), "nmethod zombie in post_compiled_method_load");
   // Add inlining information
   jvmtiCompiledMethodLoadInlineRecord* inlinerecord = create_inline_record(nm);
   // Pass inlining information through the void pointer

src/hotspot/share/prims/jvmtiImpl.cpp

@@ -962,10 +962,10 @@ JvmtiDeferredEvent JvmtiDeferredEventQueue::dequeue() {
 }
 
 void JvmtiDeferredEventQueue::post(JvmtiEnv* env) {
-  // Post and destroy queue nodes
+  // Post events while nmethods are still in the queue and can't be unloaded or made zombie
   while (_queue_head != NULL) {
-     JvmtiDeferredEvent event = dequeue();
-     event.post_compiled_method_load_event(env);
+    _queue_head->event().post_compiled_method_load_event(env);
+    dequeue();
   }
 }
 

test/hotspot/jtreg/ProblemList.txt

@@ -111,7 +111,6 @@ serviceability/jvmti/HeapMonitor/MyPackage/HeapMonitorStatIntervalTest.java 8214
 serviceability/jvmti/HeapMonitor/MyPackage/HeapMonitorStatArrayCorrectnessTest.java 8224150 generic-all
 serviceability/jvmti/ModuleAwareAgents/ThreadStart/MAAThreadStart.java 8225354 windows-all
 serviceability/dcmd/gc/RunFinalizationTest.java 8227120 linux-all,windows-x64
-serviceability/jvmti/CompiledMethodLoad/Zombie.java 8245877 linux-aarch64
 
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