Re: [PATCH v8 09/16] x86/cpufeatures: Add synthetic Secure TSC bit

[Nikunj A. Dadhania]

On 4/22/2024 6:55 PM, Borislav Petkov wrote:
> On Thu, Feb 15, 2024 at 05:01:21PM +0530, Nikunj A Dadhania wrote:
>> Add support for the synthetic CPUID flag which indicates that the SNP
>> guest is running with secure tsc enabled (MSR_AMD64_SEV Bit 11 -
> 
> "TSC"

Sure

> 
>> SecureTsc_Enabled) . This flag is there so that this capability in the
>> guests can be detected easily without reading MSRs every time accessors.
> 
> Why?
> 
> What's wrong with cc_platform_has(CC_ATTR_GUEST_SECURE_TSC) or so?
> 

That was the initial implementation, and there were review comments[1] to
use synthetic flag.

Regards
Nikunj

1. https://lore.kernel.org/lkml/20231106130041.gqoqszdxrmdomsxl@xxxxxxxxxxxxxxxxx/