Re: [PATCH v5 3/3] x86/tdx: Add Quote generation support

From: Kirill A. Shutemov
Date: Mon May 09 2022 - 21:28:56 EST


On Tue, May 10, 2022 at 11:54:12AM +1200, Kai Huang wrote:
> On Mon, 2022-05-09 at 15:09 +0300, Kirill A. Shutemov wrote:
> > On Mon, May 09, 2022 at 03:37:22PM +1200, Kai Huang wrote:
> > > On Sat, 2022-05-07 at 03:42 +0300, Kirill A. Shutemov wrote:
> > > > On Fri, May 06, 2022 at 12:11:03PM +1200, Kai Huang wrote:
> > > > > Kirill, what's your opinion?
> > > >
> > > > I said before that I think DMA API is the right tool here.
> > > >
> > > > Speculation about future of DMA in TDX is irrelevant here. If semantics
> > > > change we will need to re-evaluate all users. VirtIO uses DMA API and it
> > > > is conceptually the same use-case: communicate with the host.
> > >
> > > Virtio is designed for device driver to use, so it's fine to use DMA API. And
> > > real DMA can happen to the virtio DMA buffers. Attestation doesn't have such
> > > assumption.
> >
> > Whether attestation driver uses struct device is implementation detail.
> > I don't see what is you point.
>
> No real DMA is involved in attestation.

As with VirtIO. So what?

--
Kirill A. Shutemov