---
fixes:
  - Ironic exceptions that contained arbitrary objects in ``kwargs`` and were
    sent via RPC were causing ``oslo_messaging`` serializer to fail. This was
    leading to 500 errors from ironic API, timing out waiting for response from
    the conductor. Starting with this release, all non-serializable objects
    contained in an exception's kwargs are dropped. Whether the error is going
    to be returned by the service will depend on the configuration option
    ``[DEFAULT]/fatal_exception_format_errors``.