Merge tag 'x86_sev_for_v6.11_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 SEV updates from Borislav Petkov:

 - Add support for running the kernel in a SEV-SNP guest, over a Secure
   VM Service Module (SVSM).

   When running over a SVSM, different services can run at different
   protection levels, apart from the guest OS but still within the
   secure SNP environment. They can provide services to the guest, like
   a vTPM, for example.

   This series adds the required facilities to interface with such a
   SVSM module.

 - The usual fixlets, refactoring and cleanups

[ And as always: "SEV" is AMD's "Secure Encrypted Virtualization".

  I can't be the only one who gets all the newer x86 TLA's confused,
  can I?
              - Linus ]

* tag 'x86_sev_for_v6.11_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Documentation/ABI/configfs-tsm: Fix an unexpected indentation silly
  x86/sev: Do RMP memory coverage check after max_pfn has been set
  x86/sev: Move SEV compilation units
  virt: sev-guest: Mark driver struct with __refdata to prevent section mismatch
  x86/sev: Allow non-VMPL0 execution when an SVSM is present
  x86/sev: Extend the config-fs attestation support for an SVSM
  x86/sev: Take advantage of configfs visibility support in TSM
  fs/configfs: Add a callback to determine attribute visibility
  sev-guest: configfs-tsm: Allow the privlevel_floor attribute to be updated
  virt: sev-guest: Choose the VMPCK key based on executing VMPL
  x86/sev: Provide guest VMPL level to userspace
  x86/sev: Provide SVSM discovery support
  x86/sev: Use the SVSM to create a vCPU when not in VMPL0
  x86/sev: Perform PVALIDATE using the SVSM when not at VMPL0
  x86/sev: Use kernel provided SVSM Calling Areas
  x86/sev: Check for the presence of an SVSM in the SNP secrets page
  x86/irqflags: Provide native versions of the local_irq_save()/restore()

1 files changed, 11 insertions, 0 deletions

diff --git a/Documentation/virt/coco/sev-guest.rst b/Documentation/virt/coco/sev-guest.rst
index e1eaf6a830ce..9d00967a5b2b 100644
--- a/Documentation/virt/coco/sev-guest.rst
+++ b/Documentation/virt/coco/sev-guest.rst
@@ -204,6 +204,17 @@ 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
 ---------