Below are the cases:

jvmtiThreadState.cpp:
JvmtiVTMTDisabler::start_VTMT(jthread vthread, int callsite_tag) {
   . . .
   while (true) {
      ThreadBlockInVM tbivm(thread);
      MonitorLocker ml(JvmtiVTMT_lock, Mutex::_no_safepoint_check_flag);

      // Do not allow suspends inside VTMT transitions.
      // Block while transitions are disabled or there are suspend requests.
      if (_VTMT_disable_count > 0 ||
          thread->is_suspended() ||
          JvmtiVTSuspender::is_vthread_suspended(vth()) <== ???

jvmtiExport.cpp:
void JvmtiExport::check_suspend_at_safepoint(JavaThread *thread) {
    . . .
    // block while vthread is externally suspended
    while (JvmtiVTSuspender::is_vthread_suspended(vth())) { <== ???
      ml.wait();
    }
  }
}