Re: [PATCH v3 0/4] tdx-guest: Make Quote buffer size dynamic

[Edgecombe, Rick P]

On Wed, 2026-07-29 at 05:29 -0700, Peter Fang wrote:
> Problem
> =======
> 
> The fixed-size Quote buffer approach is not sustainable. As
> cryptographic algorithms evolve, TD Quote sizes also grow. A previous
> commit [2] increased the guest driver's fixed-size Quote buffer to 128
> KB to accommodate DICE Quotes, but it may still be insufficient when
> those Quotes use post-quantum cryptography (PQC). PQC certificate chains
> are roughly 10x-15x larger than conventional ones, which can increase
> Quote sizes significantly.

For the DICE host changes, the reason given for why the host side quote
operation is TD scoped was to avoid changing the guest by increasing the report
size. But actually, as this coverletter points out, the guest buffer sizes do
get changed. So I think we should pause this series until we sort out the
inconsistencies in the reasoning. Depending, we may want to circle back with KVM
folks on what the options actually are for the DICE quote operation.