Re: [PATCH v3 1/1] s390: virtio: let arch accept devices without IOMMU feature

Halil Pasic
2020-06-19T12:02:36Z

On Fri, 19 Jun 2020 11:20:51 +0200
Cornelia Huck <cohuck@redhat.com> wrote:

> > > + if (arch_needs_virtio_iommu_platform(dev) &&
> > > + !virtio_has_feature(dev, VIRTIO_F_IOMMU_PLATFORM)) {
> > > + dev_warn(&dev->dev,
> > > + "virtio: device must provide VIRTIO_F_IOMMU_PLATFORM\n");
> >
> > I'm not sure, divulging the current Linux name of this feature bit is a
> > good idea, but if everybody else is fine with this, I don't care that
>
> Not sure if that feature name will ever change, as it is exported in
> headers. At most, we might want to add the new ACCESS_PLATFORM define
> and keep the old one, but that would still mean some churn.
>
> > much. An alternative would be:
> > "virtio: device falsely claims to have full access to the memory,
> > aborting the device"
>
> "virtio: device does not work with limited memory access" ?
>
> But no issue with keeping the current message.

I think I prefer Conny's version, but no strong feelings here.

Halil