"Michael S. Tsirkin" [off-list ref] writes:

For small packets we can simplify xmit processing
by linearizing buffers with the header:
most packets seem to have enough head room
we can use for this purpose.
Since existing hypervisors require that header
is the first s/g element, we need a feature bit
for this.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---

Note: this needs to be applied on top of patch
defining VIRTIO_F_ANY_LAYOUT - bit to be
selected by Rusty.

The following patch should work for any definition of
VIRTIO_F_ANY_LAYOUT - I used bit 31 for testing.
Rusty, could you please pick a valid bit for VIRTIO_F_ANY_LAYOUT
and squeeze this patch into 3.11?

Sorry, it's too late.

First, I've been a bit lax in sending patches via DaveM, and this is
definitely his territory (ie. more net than virtio).

Secondly, it needs baking and testing time.

Cheers,
Rusty.