Hi Brijesh,

On 20/08/2021 18:19, Brijesh Singh wrote:

Version 2 of GHCB specification defines NAE to get the extended guest
request. It is similar to the SNP_GET_REPORT ioctl. The main difference
is related to the additional data that be returned. The additional
data returned is a certificate blob that can be used by the SNP guest
user. 

It seems like the SNP_GET_EXT_REPORT ioctl does everything that the
SNP_GET_REPORT ioctl does, and more.  Why expose SNP_GET_REPORT to
userspace at all?


-Dov

The certificate blob layout is defined in the GHCB specification.
The driver simply treats the blob as a opaque data and copies it to
userspace.

Signed-off-by: Brijesh Singh <redacted>
---
 Documentation/virt/coco/sevguest.rst  |  22 +++++
 drivers/virt/coco/sevguest/sevguest.c | 126 ++++++++++++++++++++++++++
 include/uapi/linux/sev-guest.h        |  13 +++
 3 files changed, 161 insertions(+)

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