On Mon, Dec 12, 2005 at 03:29:44PM -0500, Jeff Garzik wrote:
> John W. Linville wrote:
> >From: John W. Linville <[EMAIL PROTECTED]>
> >
> >At least some versions of the via-velocity hardware only support
> >checksumming IPv4 frames in hardware.  However, the driver is currently
> >setting the NETIF_F_HW_CSUM flag, which indicates support for more than
> >just IPv4.  This results in errors when trying to use IPv6 over
> >via-velocity hardware.

> IP_CSUM means something different than simply "ipv4-only".  It also 
> means that the hardware is quite dumb, and can only say "checksum ok" 
> rather than "here is the checksum."
> 
> Since IP_CSUM means the latter, surely you need more code than just this?

Hmmm...this would seem contrary to the following references:

        http://www.uwsg.iu.edu/hypermail/linux/net/0302.3/0003.html
        
http://efault.net/npat/docs_and_postings/net_device-features/net_device-features.txt
        http://www.oreilly.com/catalog/linuxdrive3/book/ch17.pdf

And the comment in this snippet from tg3.c:

        /* Tigon3 can do ipv4 only... and some chips have buggy
         * checksumming.
         */
        if ((tp->tg3_flags & TG3_FLAG_BROKEN_CHECKSUMS) == 0) {
                dev->features |= NETIF_F_SG | NETIF_F_IP_CSUM;
                tp->tg3_flags |= TG3_FLAG_RX_CHECKSUMS;
        } else
                tp->tg3_flags &= ~TG3_FLAG_RX_CHECKSUMS;

As well as the testimony of my user:

        https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=173760

Since the flag in question seems to be related exclusively to
transmission of frames, would a "checksum ok" even make sense?

Can you direct me to an example of the type of code that would seem
to be missing?

John
-- 
John W. Linville
[EMAIL PROTECTED]
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