From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: bisected regression: 3c59x corrupts packets in 3.17-rc5
Date: Tue, 16 Sep 2014 16:29:23 -0400 (EDT)
Message-ID: <20140916.162923.605101746131407931.davem@davemloft.net>
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From: Neil Horman <nhorman@tuxdriver.com>
Date: Tue, 16 Sep 2014 06:17:04 -0400

> I'm guessing the above change has uncovered another bug,

Neil, read your patch carefully, I think it added the bug.

The ->page_offset of the frag gets applied two times.

skb_dma_map_frag() already takes frag->page_offset into consideration,
you then pass it in as the 'offset' argument and it then gets added to
itself to compute th final offset.