Re: [PATCH v16 05/13] x86/sev: Add Secure TSC support for SNP guests

[Borislav Petkov]

On Wed, Jan 08, 2025 at 02:07:07PM +0530, Nikunj A. Dadhania wrote:
> >>  void __init snp_secure_tsc_prepare(void)
> >>  {
> >> -	if (!cc_platform_has(CC_ATTR_GUEST_SNP_SECURE_TSC))
> >> +	if (!cc_platform_has(CC_ATTR_GUEST_SEV_SNP) ||
> >> +	    !cc_platform_has(CC_ATTR_GUEST_SNP_SECURE_TSC))
> > 
> > So how is moving the CC_ATTR_GUEST_SEV_SNP check here make any sense?
> 
> In the comment that you gave here[1], I understood that this check has 
> to be pushed to snp_secure_tsc_prepare().

The check should be pushed there but you should not check
CC_ATTR_GUEST_SEV_SNP *and* CC_ATTR_GUEST_SNP_SECURE_TSC if all you wanna do
is check if you're running a STSC guest. That was the whole point.

-- 
Regards/Gruss,
    Boris.

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