From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: gso: Attempt to handle mega-GRO packets
Date: Wed, 06 Nov 2013 18:37:35 -0800
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Cc: Ben Hutchings <bhutchings@solarflare.com>,
	David Miller <davem@davemloft.net>,
	christoph.paasch@uclouvain.be, netdev@vger.kernel.org,
	hkchu@google.com, mwdalton@google.com, mst@redhat.com,
	Jason Wang <jasowang@redhat.com>
To: Herbert Xu <herbert@gondor.apana.org.au>
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On Thu, 2013-11-07 at 10:15 +0800, Herbert Xu wrote:
> On Wed, Nov 06, 2013 at 06:02:38PM -0800, Eric Dumazet wrote:
> > 
> > 4K page will contain 2 frags and they will coalesce.
> > 
> > Performance will still be quite good.
> >
> > We probably add a tweak, to not have any hole in this case.
> 
> Also have you considered the security aspect of this? If you have
> two skbs sharing a page, and one gets transmitted to a third party
> using zero-copy, the other unrelated skb's content may become visible
> where it shouldn't.

If the hypervisor is doomed, there is nothing we can do.

virtio_net owns the pages, and relies on hypervisor doing the right
thing.

That you use part of the page, is really irrelevant.

It seems you are speaking of virtio_net sending frames, but its about
receiving frames here.

We receive frames, delivered by the trusted hypervisor.

OK, I will shut up now, since apparently I really upset you.