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Diffstat (limited to 'Documentation/virt/coco/sev-guest.rst')
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diff --git a/Documentation/virt/coco/sev-guest.rst b/Documentation/virt/coco/sev-guest.rst index e1eaf6a830ce..93debceb6eb0 100644 --- a/Documentation/virt/coco/sev-guest.rst +++ b/Documentation/virt/coco/sev-guest.rst @@ -176,6 +176,25 @@ to SNP_CONFIG command defined in the SEV-SNP spec. The current values of the firmware parameters affected by this command can be queried via SNP_PLATFORM_STATUS. +2.7 SNP_VLEK_LOAD +----------------- +:Technology: sev-snp +:Type: hypervisor ioctl cmd +:Parameters (in): struct sev_user_data_snp_vlek_load +:Returns (out): 0 on success, -negative on error + +When requesting an attestation report a guest is able to specify whether +it wants SNP firmware to sign the report using either a Versioned Chip +Endorsement Key (VCEK), which is derived from chip-unique secrets, or a +Versioned Loaded Endorsement Key (VLEK) which is obtained from an AMD +Key Derivation Service (KDS) and derived from seeds allocated to +enrolled cloud service providers. + +In the case of VLEK keys, the SNP_VLEK_LOAD SNP command is used to load +them into the system after obtaining them from the KDS, and corresponds +closely to the SNP_VLEK_LOAD firmware command specified in the SEV-SNP +spec. + 3. SEV-SNP CPUID Enforcement ============================ @@ -204,6 +223,17 @@ has taken care to make use of the SEV-SNP CPUID throughout all stages of boot. Otherwise, guest owner attestation provides no assurance that the kernel wasn't fed incorrect values at some point during boot. +4. SEV Guest Driver Communication Key +===================================== + +Communication between an SEV guest and the SEV firmware in the AMD Secure +Processor (ASP, aka PSP) is protected by a VM Platform Communication Key +(VMPCK). By default, the sev-guest driver uses the VMPCK associated with the +VM Privilege Level (VMPL) at which the guest is running. Should this key be +wiped by the sev-guest driver (see the driver for reasons why a VMPCK can be +wiped), a different key can be used by reloading the sev-guest driver and +specifying the desired key using the vmpck_id module parameter. + Reference --------- |