Re: [RFC PATCH v4 11/36] i386/tdx: Initialize TDX before creating TD vcpus

[Gerd Hoffmann]

On Wed, Jun 01, 2022 at 03:20:46PM +0800, Xiaoyao Li wrote:
> On 5/24/2022 2:57 PM, Gerd Hoffmann wrote:
> >    Hi,
> > Maybe it's a bit more work to add VM-scope initialization support to
> > qemu.
> 
> If just introducing VM-scope initialization to QEMU, it would be easy. What
> matters is what needs to be done inside VM-scope initialization.
> 
> For TDX, we need to settle down the features that configured for the TD.
> Typically, the features are attributes of cpu object, parsed from "-cpu"
> option and stored in cpu object.

> 2) create a CPU object when initializing machine object and collect all the
> info from "-cpu" and drop it in the end; then why not do it when creating
> 1st vcpu like this patch.

Do VM-scope tdx initialization late enough that cpu objects are already
created at that point, so you can collect the info you need without a
dummy cpu?

I guess it could be helpful for the discussion when you can outine the
'big picture' for tdx initialization.  How does kvm accel setup look
like without TDX, and what additional actions are needed for TDX?  What
ordering requirements and other constrains exist?

take care,
  Gerd