[PATCH 0/3] virtio: Clean up scatterlists and use the DMA API

Stefan Hajnoczi
Wed, 27 Aug 2014 06:46:46 -0000

On Tue, Aug 26, 2014 at 10:16 PM, Andy Lutomirski <luto at amacapital.net>
wrote:
> There are two outstanding issues.  virtio_net warns if DMA debugging
> is on because it does DMA from the stack.  (The warning is correct.)
> This also is likely to do something unpleasant to s390.
> (Maintainers are cc'd -- I don't know what to do about it.)

This changes the semantics of vring and breaks existing guests when
bus address != physical address.

Can you use a transport feature bit to indicate that bus addresses are
used?  That way both approaches can be supported.

Please also update the virtio specification:
https://tools.oasis-open.org/version-control/browse/wsvn/virtio/

Stefan