Re: gre tunnel problem

[David Young <dyoung%pobox.com@localhost>]

On Thu, Oct 27, 2011 at 12:03:53PM -0500, David Young wrote:
> I have discovered that wm(4)'s IPv4 checksum offload (ifconfig wm0
> ip4csum) interferes with IPv6 transmission through gre(4).  I realize
> that IPv6 is not your problem, but it does make me wonder whether more
> offload problems lurk.

The interference between checksum-offload and tunnels was in gre(4).
gif(4) was affected, too.  Fixed in -current.

The reason that bnx(4) worked and wm(4) didn't with the ip4csum-tx
option was that bnx(4) didn't use csum_data, but wm(4) did.  Now gre(4)
and gif(4) zero both csum_data and csum_flags.

Dave

-- 
David Young             OJC Technologies is now Pixo
dyoung%pixotech.com@localhost     Urbana, IL   (217) 344-0444 x24