[PATCH v1 1/8] docs: documentation and schema for the new TPM Proxy device

[Daniel P. Berrangé]

On Tue, May 12, 2020 at 11:21:52AM -0400, Stefan Berger wrote:
> On 5/11/20 7:28 AM, Daniel P. Berrangé wrote:
> > On Mon, May 11, 2020 at 08:26:53AM -0300, Daniel Henrique Barboza wrote:
> > > 
> > > On 5/11/20 6:57 AM, Daniel P. Berrangé wrote:
> > > > On Mon, May 11, 2020 at 11:22:57AM +1000, David Gibson wrote:
> > > [...]
> > > > > It's a different guest side interface, the H_TPM_COMM hypercall
> > > > > instead of the other PAPR TPM interface.  To which "why?" is a very
> > > > > good question, but it's there now, so there's not much we can do about
> > > > > it.
> > > > That's ok. Even though its a different guest interface, it is still
> > > > conceptually a TPM device at a high level, so we should be reusing
> > > > the existing <tpm> device type. At most we should add a new backend
> > > > type
> > > I think adding a new backend type is sensible. Re-using the passthrough type
> > > and making the differentiation with 'model', for a device that doesn't
> > > operate exactly as a regular vTPM but can coexist with other vTPM devices,
> > > will make for a lot of IFs in the code.
> > Currently libvirt only allows a single <tpm>, but we can trivially
> > lift that restriction to allow multiple if desired too.
> 
> 
> QEMU won't accept multiple TIS or CRB devices, though.

The commit message says you can do 2 at a time:

  "Although redundant, there is currently no technical
   limitation for a guest to assign both a vTPM and a TPM Proxy at the
   same time."

is that text not accurate ?

Regards,
Daniel
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