Re: [PATCH v5 09/12] x86/tdx: Wire up KVM hypercalls

From: Borislav Petkov
Date: Tue Aug 24 2021 - 15:38:49 EST


On Tue, Aug 24, 2021 at 12:11:00PM -0700, Kuppuswamy, Sathyanarayanan wrote:
> If the TDX code is complied for another hypervior, we need some config to
> disable above the above code.

Isn't that what CONFIG_KVM_GUEST is for?

Also, if they don't get used anywhere, the compiler will simply discard
them. I still don't see the need for the ifdeffery.

> Following is the error info.
>
> WARNING: modpost: EXPORT symbol "__tdx_hypercall" [vmlinux] version
> generation failed, symbol will not be versioned.
>
> So to fix the above issue, added tdx.h in arch/x86/include/asm/asm-prototypes.h

You need the C-style declaration of __tdx_hypercall, see

334bb7738764 ("x86/kbuild: enable modversions for symbols exported from asm")

and you can do the include without the ifdeffery.

And also state in the commit message why you're including it.

Thx.

--
Regards/Gruss,
Boris.

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