Re: [PATCH V1 3/6] xen/virtio: Add option to restrict memory access under Xen

From: Christoph Hellwig
Date: Mon Apr 25 2022 - 03:59:08 EST

On Mon, Apr 25, 2022 at 09:47:49AM +0200, Juergen Gross wrote:
> > Would the Xen specific bits fit into Confidential Computing Platform
> > checks? I will let Juergen/Boris comment on this.
> I don't think cc_platform_has would be correct here. Xen certainly
> provides more isolation between guests and dom0, but "Confidential
> Computing" is basically orthogonal to that feature.

The point of cc_platform_has is to remove all these open code checks.
If a Xen hypervisor / dom0 can't access arbitrary guest memory for
virtual I/O and we need special APIs for that it certainly false
into the scope of cc_platform_has, even if the confientiality is
rather limited.