From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael Chan" <mchan@broadcom.com>
Subject: Re: [PATCH 3/20][BNX2]: Add 40-bit DMA workaround for 5708.
Date: Wed, 02 May 2007 11:23:52 -0700
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 <4638AE42.5000908@garzik.org>
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Cc: "David Miller" <davem@davemloft.net>,
	"netdev" <netdev@vger.kernel.org>
To: "Jeff Garzik" <jeff@garzik.org>
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On Wed, 2007-05-02 at 11:29 -0400, Jeff Garzik wrote:
> Michael Chan wrote:
> > A non-IOMMU system using 64-bit dma_addr_t will always set
> > CONFIG_HIGHMEM, right?
> 
> No.
> 
May be I misunderstood the code in illegal_highdma() in net/core/dev.c
where it is checking to see if it needs to linearize the SKB when the
device does not support 64-bit DMA.  I'm using similar assumptions for
the 40-bit address check in the patch.