[PATCH 03/10] Documentation: kvm/sev: separate description of firmware

From: Paolo Bonzini
Date: Fri Feb 09 2024 - 13:38:57 EST


The description of firmware is included part under the "SEV Key Management"
header, part under the KVM_SEV_INIT ioctl. Put these two bits together and
and rename "SEV Key Management" to what it actually is, namely a description
of the KVM_MEMORY_ENCRYPT_OP API.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
.../virt/kvm/x86/amd-memory-encryption.rst | 29 +++++++++++--------
1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/Documentation/virt/kvm/x86/amd-memory-encryption.rst b/Documentation/virt/kvm/x86/amd-memory-encryption.rst
index 995780088eb2..37c5c37f4f6e 100644
--- a/Documentation/virt/kvm/x86/amd-memory-encryption.rst
+++ b/Documentation/virt/kvm/x86/amd-memory-encryption.rst
@@ -46,14 +46,8 @@ SEV hardware uses ASIDs to associate a memory encryption key with a VM.
Hence, the ASID for the SEV-enabled guests must be from 1 to a maximum value
defined in the CPUID 0x8000001f[ecx] field.

-SEV Key Management
-==================
-
-The SEV guest key management is handled by a separate processor called the AMD
-Secure Processor (AMD-SP). Firmware running inside the AMD-SP provides a secure
-key management interface to perform common hypervisor activities such as
-encrypting bootstrap code, snapshot, migrating and debugging the guest. For more
-information, see the SEV Key Management spec [api-spec]_
+``KVM_MEMORY_ENCRYPT_OP`` API
+=============================

The main ioctl to access SEV is KVM_MEMORY_ENCRYPT_OP. If the argument
to KVM_MEMORY_ENCRYPT_OP is NULL, the ioctl returns 0 if SEV is enabled
@@ -87,10 +81,6 @@ guests, such as launching, running, snapshotting, migrating and decommissioning.
The KVM_SEV_INIT command is used by the hypervisor to initialize the SEV platform
context. In a typical workflow, this command should be the first command issued.

-The firmware can be initialized either by using its own non-volatile storage or
-the OS can manage the NV storage for the firmware using the module parameter
-``init_ex_path``. If the file specified by ``init_ex_path`` does not exist or
-is invalid, the OS will create or override the file with output from PSP.

Returns: 0 on success, -negative on error

@@ -434,6 +424,21 @@ issued by the hypervisor to make the guest ready for execution.

Returns: 0 on success, -negative on error

+Firmware Management
+===================
+
+The SEV guest key management is handled by a separate processor called the AMD
+Secure Processor (AMD-SP). Firmware running inside the AMD-SP provides a secure
+key management interface to perform common hypervisor activities such as
+encrypting bootstrap code, snapshot, migrating and debugging the guest. For more
+information, see the SEV Key Management spec [api-spec]_
+
+The AMD-SP firmware can be initialized either by using its own non-volatile
+storage or the OS can manage the NV storage for the firmware using
+parameter ``init_ex_path`` of the ``ccp`` module. If the file specified
+by ``init_ex_path`` does not exist or is invalid, the OS will create or
+override the file with PSP non-volatile storage.
+
References
==========

--
2.39.0