[PATCH v3 03/10] x86/sev: Set GHCB data structure version

Joerg Roedel
2022-01-27T10:11:36Z

It turned out that the GHCB->protocol field does not declare the
version of the guest-hypervisor communication protocol, but rather the
version of the GHCB data structure. Reflect that in the define used to
set the protocol field.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
arch/x86/include/asm/sev.h | 3 +++
arch/x86/kernel/sev-shared.c | 2 +-
2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h
index 17b75f6ee11a..09eb2cc6f54f 100644
--- a/arch/x86/include/asm/sev.h
+++ b/arch/x86/include/asm/sev.h
@@ -16,6 +16,9 @@
#define GHCB_PROTOCOL_MAX 2ULL
#define GHCB_DEFAULT_USAGE 0ULL

+/* Version of the GHCB data structure */
+#define GHCB_VERSION 1
+
#define VMGEXIT() { asm volatile("rep; vmmcall\n\r"); }

enum es_result {
diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c
index 60ca7dd64d64..4468150a42bb 100644
--- a/arch/x86/kernel/sev-shared.c
+++ b/arch/x86/kernel/sev-shared.c
@@ -162,7 +162,7 @@ enum es_result sev_es_ghcb_hv_call(struct ghcb *ghcb, bool set_ghcb_msr,
u64 exit_info_1, u64 exit_info_2)
{
/* Fill in protocol and format specifiers */
- ghcb->protocol_version = GHCB_PROTOCOL_MAX;
+ ghcb->protocol_version = GHCB_VERSION;
ghcb->ghcb_usage = GHCB_DEFAULT_USAGE;

ghcb_set_sw_exit_code(ghcb, exit_code);
--
2.34.1