Re: [PATCH v8 5/5] x86/tdx: Add Quote generation support

Dave Hansen
2022-07-22T00:27:16Z

On 6/8/22 19:52, Kuppuswamy Sathyanarayanan wrote:
> In TDX guest, the second stage in attestation process is to send the
> TDREPORT to QE/QGS to generate the TD Quote. For platforms that does
> not support communication channels like vsock or TCP/IP, implement
> support to get TD Quote using hypercall. GetQuote hypercall can be used
> by the TD guest to request VMM facilitate the Quote generation via
> QE/QGS. More details about GetQuote hypercall can be found in TDX
> Guest-Host Communication Interface (GHCI) for Intel TDX 1.0, section
> titled "TDG.VP.VMCALL<GetQuote>.

So, the quote portion of this is basically a bidirectional blob sender.
It's to send a blob between guest userspace to host userspace.

Do we *REALLY* need specific driver functionality for this? For
instance, is there no existing virtio device that can send blobs back
and forth?