Re: [PATCH v3 08/21] x86/virt/tdx: Do logical-cpu scope TDX module initialization

From: Kai Huang
Date: Mon Apr 25 2022 - 19:56:09 EST


On Sat, 2022-04-23 at 18:27 -0700, Sathyanarayanan Kuppuswamy wrote:
>
> On 4/5/22 9:49 PM, Kai Huang wrote:
> > Logical-cpu scope initialization requires calling TDH.SYS.LP.INIT on all
> > BIOS-enabled cpus, otherwise the TDH.SYS.CONFIG SEAMCALL will fail.
>
> IIUC, this change handles logical CPU initialization part of TDX module
> initialization. So why talk about TDH.SYS.CONFIG failure here? Are they
> related?

They are a little bit related but I think I can remove it. Thanks.

>
> > TDH.SYS.LP.INIT can be called concurrently on all cpus.
>
> IMO, if you move the following paragraph to the beginning, it is easier
> to understand "what" and "why" part of this change.

OK.

> >
> > Following global initialization, do the logical-cpu scope initialization
> > by calling TDH.SYS.LP.INIT on all online cpus. Whether all BIOS-enabled
> > cpus are online is not checked here for simplicity. The caller of
> > tdx_init() should guarantee all BIOS-enabled cpus are online.
>
> Include specification reference for TDX module initialization and
> TDH.SYS.LP.INIT.
>
> In TDX module spec, section 22.2.35 (TDH.SYS.LP.INIT Leaf), mentions
> some environment requirements. I don't see you checking here for it?
> Is this already met?
>

Good catch. I missed it, and I'll look into it. Thanks.


--
Thanks,
-Kai