Re: [PATCH 0/2] virtio: non-legacy device handling

[David Hildenbrand]

On 07.07.20 12:54, Cornelia Huck wrote:
> As discussed in "virtio-fs: force virtio 1.x usage", it seems like
> a good idea to make sure that any new virtio device (which does not
> support legacy virtio) is indeed a non-transitional device, just to
> catch accidental misconfigurations. We can easily compile a list
> of virtio devices with legacy support and have transports verify
> in their plugged callbacks that legacy support is off for any device
> not in that list.
> 
> Most new virtio devices force non-transitional already, so nothing
> changes for them. vhost-user-fs-pci even does not allow to configure
> a non-transitional device, so it is fine as well.
> 
> One problematic device, however, is virtio-iommu-pci. It currently
> offers both the transitional and the non-transitional variety of the
> device, and does not force anything. I'm unsure whether we should
> consider transitional virtio-iommu unsupported, or if we should add
> some compat handling. (The support for legacy or not generally may
> change based upon the bus, IIUC, so I'm unsure how to come up with
> something generic.)
> 
> Cornelia Huck (2):
>   virtio: list legacy-capable devices
>   virtio: verify that legacy support is not accidentally on

I'd squash both patches. Looking at patch #1, I wonder why we don't
store that information along with the device implementation? What was
the motivation to define this information separately?


-- 
Thanks,

David / dhildenb