74458e4859
Version 2 of GHCB specification added support for the SNP Extended Guest Request Message NAE event. This event serves a nearly identical purpose to the previously-added SNP_GUEST_REQUEST event, but for certain message types it allows the guest to supply a buffer to be used for additional information in some cases. Currently the GHCB spec only defines extended handling of this sort in the case of attestation requests, where the additional buffer is used to supply a table of certificate data corresponding to the attestion report's signing key. Support for this extended handling will require additional KVM APIs to handle coordinating with userspace. Whether or not the hypervisor opts to provide this certificate data is optional. However, support for processing SNP_EXTENDED_GUEST_REQUEST GHCB requests is required by the GHCB 2.0 specification for SNP guests, so for now implement a stub implementation that provides an empty certificate table to the guest if it supplies an additional buffer, but otherwise behaves identically to SNP_GUEST_REQUEST. Reviewed-by: Carlos Bilbao <carlos.bilbao.osdev@gmail.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Liam Merwick <liam.merwick@oracle.com> Signed-off-by: Michael Roth <michael.roth@amd.com> Message-ID: <20240701223148.3798365-4-michael.roth@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.