The JDK-8319935 crashes cannot reproduce consistently, which makes it difficult to write a simple reproducible test. As one possible option, we could add a WhiteBox api to iterate the JvmtiThreadState list and validate if all the JavaThread pointers are still valid after threads detaching. The test needs to create native threads to attach and detach before the check. That could verify the 1-1 mapping of JvmtiThreadState and JavaThread.