And I from your code in xenpci_pdo.c as follow:

    if (XenPci_ChangeFrontendState(xppdd, XenbusStateConnected, 
XenbusStateConnected, 30000) != STATUS_SUCCESS)
    {
      _// this is definitely an unrecoverable situation..._
      KdPrint((__DRIVER_NAME "     Failed to change frontend state to 
connected\n"));
      FUNCTION_ERROR_EXIT();
      return STATUS_UNSUCCESSFUL;
    }

I think I got this situation. How did you avoid that?

Thanks,
Wayne