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

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.