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Surely they can do better. > In myy understanding for for MAC timestamping, the igc hardware stores the timestamp in a register and assumes you only have one outstanding timestamp request at a time. The MAC timestamp is captured well after the Tx descriptor is written back as complete. There's no completion queue on this device to send such a message out-of-band of the Tx writeback. Delaying the writeback until after the Tx timestamp is captured would have its own challenges. Obviously it *can* be done better than this, but thats not how the igc hardware was designed.