ThreadContainers are accessed by both virtual threads and carriers. If a virtual thread were to block/park and unmount then it could deadlock.

Patricio observed the following stack trace for many threads when running Skynet, the threads are in the BLOCKED state.

java.base/java.util.concurrent.ConcurrentHashMap.treeifyBin(ConcurrentHashMap.java:2691)
java.base/java.util.concurrent.ConcurrentHashMap.putVal(ConcurrentHashMap.java:1080)
java.base/java.util.concurrent.ConcurrentHashMap$KeySetView.add(ConcurrentHashMap.java:4672)
java.base/jdk.internal.vm.ThreadContainers$RootContainer$TrackingRootContainer.onStart(ThreadContainers.java:248)
java.base/java.lang.VirtualThread.start(VirtualThread.java:710)
java.base/java.lang.VirtualThread.start(VirtualThread.java:728)
java.base/java.lang.ThreadBuilders$VirtualThreadBuilder.start(ThreadBuilders.java:262)