Java Update 8u102 Deadlocks WebStart Applications

The recent Java update 8u102 has a sever bug which deadlocks WebStart applications in jdk internal class loading. The Bug has been reported but is not completly visible in the java bug database.

The thread dump will show a pattern like the following if you are hit by this bug:

java.lang.Thread.State: BLOCKED (on object monitor)

          at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)

          - waiting to lock <0x________> (a com.sun.jnlp.JNLPClassLoader)

 

Setting the vm flag -XX:+AlwaysLockClassLoader in the java deployment console does not help.
The java security update version 8u101 is not affected by this bug.