Re: [PATCH v6 0/5] Add Guest API & Guest Kernel support for SEV live migration.

[Paolo Bonzini]

On 8/24/21 13:03, Ashish Kalra wrote:
> adds guest api and guest kernel support for SEV live migration.
>
> The patch series introduces a new hypercall. The guest OS can use this
> hypercall to notify the page encryption status. If the page is encrypted
> with guest specific-key then we use SEV command during the migration.
> If page is not encrypted then fallback to default. This new hypercall
> is invoked using paravirt_ops.
>
> This section descibes how the SEV live migration feature is negotiated
> between the host and guest, the host indicates this feature support via
> KVM_FEATURE_CPUID. The guest firmware (OVMF) detects this feature and
> sets a UEFI enviroment variable indicating OVMF support for live
> migration, the guest kernel also detects the host support for this
> feature via cpuid and in case of an EFI boot verifies if OVMF also
> supports this feature by getting the UEFI enviroment variable and if it
> set then enables live migration feature on host by writing to a custom
> MSR, if not booted under EFI, then it simply enables the feature by
> again writing to the custom MSR.

Queued, thanks.

Paolo