On Fri, 24 Oct 2014 10:38:39 +0200 Cornelia Huck <cornelia.huck@xxxxxxxxxx> wrote: > On Fri, 24 Oct 2014 00:42:20 +0300 > "Michael S. Tsirkin" <mst@xxxxxxxxxx> wrote: > > > On Tue, Oct 07, 2014 at 04:39:56PM +0200, Cornelia Huck wrote: > > > This patchset aims to get us some way to implement virtio-1 compliant > > > and transitional devices in qemu. Branch available at > > > > > > git://github.com/cohuck/qemu virtio-1 > > > > > > I've mainly focused on: > > > - endianness handling > > > - extended feature bits > > > - virtio-ccw new/changed commands > > > > So issues identified so far: > > Thanks for taking a look. > > > - devices not converted yet should not advertize 1.0 > > Neither should an uncoverted transport. So we either can > - have transport set the bit and rely on devices ->get_features > callback to mask it out > (virtio-ccw has to change the calling order for get_features, btw.) > - have device set the bit and the transport mask it out later. Feels a > bit weird, as virtio-1 is a transport feature bit. > > I'm tending towards the first option; smth like this (on top of my > branch): (...) OK, I played around with this patch on top and the vhost-next branch as guest. It seems to work reasonably well so far: a virtio-blk device used virtio-1, a virtio-balloon device legacy. One thing I noticed, though, is that I may need to think about virtio-ccw revision vs. virtio version again. As a device can refuse virtio-1 after the driver negotiated revision 1, we're operating a legacy device with (some) standard ccws. Probably not a big deal, as (a) both driver and device already have indicated that they support revision 1 which those ccws are tied to and (b) some legacy devices/drivers already support standard ccws (adapter interrupt support). I might want to clarify the standard a bit, let me think about that over the weekend. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
