From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: Dropping NETIF_F_SG since no checksum feature.
Date: Wed, 11 Oct 2006 02:20:15 -0700 (PDT)
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From: "Michael S. Tsirkin" <mst@mellanox.co.il>
Date: Wed, 11 Oct 2006 11:05:04 +0200

> So, it seems that if I set NETIF_F_SG but clear NETIF_F_ALL_CSUM,
> data will be copied over rather than sent directly.
> So why does dev.c have to force set NETIF_F_SG to off then?

Because it's more efficient to copy into a linear destination
buffer of an SKB than page sub-chunks when doing checksum+copy.