On Thu, 2008-05-01 at 19:12 +0800, Herbert Xu wrote:

On Thu, May 01, 2008 at 12:08:48PM +0100, Kieran Mansley wrote:

quoted

Yes, everything works fine in that case.  It's only when LRO packets are
forwarded to another physical interface that things go wrong.  

Now this is definitely broken because it fiddles with TCP packets
in the middle, but still it should *work* in as much as making the
packet go out.  Well except that you need to fix up the checksum
so that it only contains the pseudo-header on output.  That's
probably what you need to address if we failed in avoiding LRO
on forwarded traffic.

If I remember rightly it also gets upset when it comes to split the
packet because the frag_list is already in use; it expects this not to
be the case for GSO but it's valid for an LRO packet to do this I think.
I don't think there's anything fundamentally difficult here, it's just
that the code has never been written to cope.

Kieran