Re: [PATCH V6 2/5] x86/hyper-v: Add hyperv Isolation VM check in the cc_platform_has()

Tianyu Lan
2021-12-07T11:18:32Z

Hi Borislav:
Thanks for your review.

On 12/7/2021 5:47 PM, Borislav Petkov wrote:
> On Tue, Dec 07, 2021 at 02:55:58AM -0500, Tianyu Lan wrote:
>> From: Tianyu Lan <Tianyu.Lan@microsoft.com>
>>
>> Hyper-V provides Isolation VM which has memory encrypt support. Add
>> hyperv_cc_platform_has() and return true for check of GUEST_MEM_ENCRYPT
>> attribute.
>
> You need to refresh on how to write commit messages - never say what the
> patch is doing - that's visible in the diff itself. Rather, you should
> talk about *why* it is doing what it is doing.

Sure. Will update.

>
>> bool cc_platform_has(enum cc_attr attr)
>> {
>> + if (hv_is_isolation_supported())
>> + return hyperv_cc_platform_has(attr);
>
> Is there any reason for the hv_is_.. check to come before...
>

Do you mean to check hyper-v before sev? If yes, no special reason.

>> +
>> if (sme_me_mask)
>> return amd_cc_platform_has(attr);
>
> ... the sme_me_mask check?
>
> What's in sme_me_mask on hyperv?

sme_me_mask is unset in this case.