Subject: Re: [PATCH 3/20][BNX2]: Add 40-bit DMA workaround for 5708.

From: "Michael Chan" <[email-masked]>
Date: Wed, 02 May 2007 11:23:52 -0700

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.