Re: [Qemu-devel] [PATCH] target/i386: sev: add 'sev-max-guests' field to 'query-sev-capabilities'

[Erik Skultety]

On Fri, Apr 12, 2019 at 10:26:45AM +0200, Paolo Bonzini wrote:
> On 12/04/19 10:19, Erik Skultety wrote:
> >> Since this field is not specific to guest configuration, I don't think
> >> it belongs in query-sev-capabilities; QEMU does not care about >1 guest.
> > Neither pdh nor cert-chain are specific to the guest config.
>
> Sort of, they are required to start a guest, aren't they?  But the

Unless you're interested in the measurement, aka attestation, I don't think
those are required in any way.

Erik

> number of guests is irrelevant.
>
> > I see why this
> > should be better suited for query-sev, the same goes for libvirt - I think 
> > we
> > shouldn't have gone with reporting the SEV platform caps in domain 
> > capabilities,
> > we should have IMHO report it both in the host capabilities (platform 
> > specific
> > stuff) and in domain capabilities to indicate that both libvirt and QEMU
> > support the SEV feature. Having said that, we have a precedent which I think
> > we might be better off with following rather than splitting the information
> > among multiple commands.
>
> For Libvirt, sure.  But I think this doesn't belong in QEMU at all.
> Libvirt should just use CPUID.
>
> Paolo