From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: BUG in netxen_release_tx_buffers when TSO enabled on kernels
 >= 3.3 and <= 3.6
Date: Tue, 22 Jan 2013 11:59:42 -0800
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Cc: christoph.paasch@uclouvain.be,
	Ian Campbell <Ian.Campbell@citrix.com>,
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	Rajesh Borundia <rajesh.borundia@qlogic.com>,
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To: Ben Hutchings <bhutchings@solarflare.com>
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On Tue, 2013-01-22 at 19:36 +0000, Ben Hutchings wrote:

> There's another bug right here, which is that 0 is a valid DMA address
> in some systems.  The driver should be calling pci_dma_mapping_error()
> to find out whether an address is valid or not.  But it also wants to be
> able to assign an invalid address to netxen_skb_frag::dma, and
> unfortunately there is no way to do that in the current DMA API.
> 

I guess we should only test ->frag_count then, and set it to 0 in TX
completion path.