On 15/09/2015 18:44, Cornelia Huck wrote: >> > Can you explain why? If there is any non-zero valid length, "wildcard >> > length" (represented by zero) would also make sense. > What is a wildcard match supposed to mean in this case? The datamatch > field contains the queue index for the device specified in the address > field. The hypercall interface associated with the eventfd always has > device + queue index in its parameters; there is no interface for > "notify device with all its queues".
Ah, I see. Because all valid virtio-ccw ioeventfds are datamatch, no valid virtio-ccw ioeventfd is wildcard-length. Paolo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/