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Date:   Thu, 2 Nov 2023 11:11:52 +0530
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Reply-To: nikunj@amd.com
Subject: Re: [PATCH v5 09/14] x86/sev: Add Secure TSC support for SNP guests
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To:     Tom Lendacky <thomas.lendacky@amd.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
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        dave.hansen@linux.intel.com, dionnaglaze@google.com,
        pgonda@google.com, seanjc@google.com, pbonzini@redhat.com
References: <20231030063652.68675-1-nikunj@amd.com>
 <20231030063652.68675-10-nikunj@amd.com>
 <b5e71977-abf6-aa27-3a7b-37230b014724@amd.com>
From:   "Nikunj A. Dadhania" <nikunj@amd.com>
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On 10/31/2023 1:56 AM, Tom Lendacky wrote:
>> diff --git a/include/linux/cc_platform.h b/include/linux/cc_platform.h
>> index cb0d6cd1c12f..e081ca4d5da2 100644
>> --- a/include/linux/cc_platform.h
>> +++ b/include/linux/cc_platform.h
>> @@ -90,6 +90,14 @@ enum cc_attr {
>>        * Examples include TDX Guest.
>>        */
>>       CC_ATTR_HOTPLUG_DISABLED,
>> +
>> +    /**
>> +     * @CC_ATTR_GUEST_SECURE_TSC: Secure TSC is active.
>> +     *
>> +     * The platform/OS is running as a guest/virtual machine and actively
>> +     * using AMD SEV-SNP Secure TSC feature.
> 
> I think TDX also has a secure TSC like feature, so can this be generic?

Yes, we can do that. In SNP case SecureTSC is an optional feature, not sure if that is the case for TDX as well.

Kirill any inputs ?

> 
> Thanks,
> Tom
> 
>> +     */
>> +    CC_ATTR_GUEST_SECURE_TSC,
>>   };
>>     #ifdef CONFIG_ARCH_HAS_CC_PLATFORM 

Regards
Nikunj