This problem has two sides. One is that the `VirtualThread::run() `cashes the field `notifyJvmtiEvents` value. It caused the native method `notifyJvmtiUnmountBegin()` not called after the field `notifyJvmtiEvents` value has been set to `true` when an agent library is loaded into running VM. The fix is to get rid of this cashing. Another is that enabling `notifyJvmtiEvents` notifications needs a synchronization. Otherwise, a VTMS transition start can be missed which will cause some asserts to fire. The fix is to use a JvmtiVTMSTransitionDisabler helper for sync.
Testing: The originally failed tests are passed now: runtime/vthread/RedefineClass.java runtime/vthread/TestObjectAllocationSampleEvent.java In progress: Run the tiers 1-6 to make sure there are no regression. ------------- Commit messages: - 8297286: runtime/vthread tests crashing after JDK-8296324 Changes: https://git.openjdk.org/jdk/pull/11304/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11304&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8297286 Stats: 6 lines in 3 files changed: 1 ins; 3 del; 2 mod Patch: https://git.openjdk.org/jdk/pull/11304.diff Fetch: git fetch https://git.openjdk.org/jdk pull/11304/head:pull/11304 PR: https://git.openjdk.org/jdk/pull/11304
