RX fencing allows the driver to know that any prior change to the RQs has finished, e.g. when the RQs are disabled/enabled or the hashkey/indirection table are changed, RX fencing is required. Remove the previous 'sleep' workaround and add the real support for RX fencing as the PF driver supports the MANA_FENCE_RQ request now (any old PF driver not supporting the request won't be used in production). MFC after: 2 weeks Sponsored by: Microsoft