We started to see what looks like a JPA extended persistence context
related error.  is the server.log that shows the exception (see the
last one near the bottom) that shouldn't be happening on WildFly master.
Also, there are some marshalling errors that I didn't see on brontes
(I'm wondering if there is a concurrency error between the bean
invocation and passivation/activation when Hibernate throws the
"java.lang.IllegalStateException: Cannot serialize a session while
connected" error during marshalling as if bean is active).
I am able to recreate the failure locally with a modification to the
PassivationTestCase.testPassivationMaxSize()  to repeatedly
alternative between calls to remote1 + remote2 beans.
I don't have this nailed down to the actual cause but it seems like a
race condition between passivation/activation and bean invocation (imo).
results from more than one test run. If you look at the server.log, you
probably should go to the end and see the last "javax.ejb.EJBException:
WFLYJPA0030: Found extended persistence context in SFSB invocation call
stack but that cannot be used" error
 unit test change to loop repeatedly until failure occurs