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If we enable > the KEEP_CRC offload, then the > NIC is supposed to preserve the CRC in the packet, that much is clear. > But we checked other drivers > and it seems common for PMDs to remove the CRC from the final mbufs. Why > is that? > > We couldn't find any place where the CRC would be stored after removal, > so it looks like the application > doesn't have access to this piece of data. And if so, what's the point > of having this feature if the CRC > is discarded either way? > > We're probably missing something and would really appreciate any help > with this. > Hi Viacheslav, As you said default behavior is to strip the CRC from packet, even some devices doesn't support having CRC in the packet it is removed by HW automatically. In this case application can't access to the CRC. For the devices that has capability to keep CRC, KEEP_CRC offload should enable having CRC as part of the packet. There is no special field to store the CRC.