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Date: Sun, 18 Sep 2011 20:23:03 -0400
From: "Dieter BSD" <dieterbsd@engineer.com>
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Subject: Re: checksum offload
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> The data sheet for intel 82576 advertises IP TX/RX checksum offload
> but the driver does not set CSUM_IP in ifp->if_hwassist. Does this mean that
> driver (and chip) do not support IP TX checksum offload or the support for
> TX is not yet included in the driver?

The first question is "is checksum offload a good idea?"
There is less protection against errors.