Re: [PATCH v8 02/11] x86/tdx: Introduce INTEL_TDX_GUEST config option

From: Borislav Petkov
Date: Tue Oct 05 2021 - 13:29:43 EST


On Tue, Oct 05, 2021 at 07:48:25AM -0700, Kuppuswamy, Sathyanarayanan wrote:
> Since x2APIC will always exist in TDX guest case, we have used select to
> enable the support. But since we have dependency on it, I think "depends"
> might be a better choice.

Right, and while we're on the subject, this looks silly to me too:

+ depends on SECURITY
...
+ select SECURITY_LOCKDOWN_LSM

because

Symbol: SECURITY_LOCKDOWN_LSM [=n]
│ Type : bool
│ Defined at security/lockdown/Kconfig:1
│ Prompt: Basic module for enforcing kernel lockdown
│ Depends on: SECURITY [=n]
^^^^^^^^^

so that symbol already depends on SECURITY.

And I have SECURITY=n in my config so I still have to go select SECURITY
by hand so that CONFIG_INTEL_TDX_GUEST becomes visible. And when I
select it, SECURITY_LOCKDOWN_LSM gets enabled too.

But since I have to go select SECURITY, I can just as well enable
SECURITY_LOCKDOWN_LSM in order to have TDX guest support.

IOW, I don't see the point for the evil "select"s - just make everything
depends on and be done with it.

Unless there's an aspect I'm missing...

Thx.

--
Regards/Gruss,
Boris.

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