[PATCH v3 3/9] target/i386: SEV: Consolidate SEV feature validation to common init path

["Naveen N Rao (AMD)" <naveen@kernel.org>]

Currently, check_sev_features() is called in multiple places when
processing IGVM files: both when processing the initial VMSA SEV
features from IGVM, as well as when validating the full contents of the
VMSA. Move this to a single point in sev_common_kvm_init() to simplify
the flow, as well as to re-use this function when VMSA SEV features are
being set without using IGVM files.

Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Naveen N Rao (AMD) <naveen@kernel.org>
---
 target/i386/sev.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/target/i386/sev.c b/target/i386/sev.c
index 7cfd15238703..89cde2c6464a 100644
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -595,9 +595,6 @@ static int check_vmsa_supported(SevCommonState *sev_common, hwaddr gpa,
     vmsa_check.x87_fcw = 0;
     vmsa_check.mxcsr = 0;
 
-    if (check_sev_features(sev_common, vmsa_check.sev_features, errp) < 0) {
-        return -1;
-    }
     vmsa_check.sev_features = 0;
 
     if (!buffer_is_zero(&vmsa_check, sizeof(vmsa_check))) {
@@ -1918,6 +1915,10 @@ static int sev_common_kvm_init(ConfidentialGuestSupport *cgs, Error **errp)
             }
         }
 
+        if (check_sev_features(sev_common, sev_common->sev_features, errp) < 0) {
+            return -1;
+        }
+
         /*
          * KVM maintains a bitmask of allowed sev_features. This does not
          * include SVM_SEV_FEAT_SNP_ACTIVE which is set accordingly by KVM
@@ -2537,9 +2538,6 @@ static int cgs_set_guest_state(hwaddr gpa, uint8_t *ptr, uint64_t len,
                            __func__);
                 return -1;
             }
-            if (check_sev_features(sev_common, sa->sev_features, errp) < 0) {
-                return -1;
-            }
             sev_common->sev_features = sa->sev_features;
         }
         return 0;
-- 
2.51.0