From: Xiaoyao Li <xiaoyao.li@intel.com>

The error message is misleading - we successfully decoded the data,
the decoded data was simply with the wrong length.

Change the error message to show it is an length check failure with both
the received and expected values.

Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Link: https://lore.kernel.org/r/20250603050305.1704586-4-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/kvm/tdx.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index acbe7497543..2284167141a 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -1032,7 +1032,9 @@ int tdx_pre_create_vcpu(CPUState *cpu, Error **errp)
             return -1;
         }
         if (data_len != QCRYPTO_HASH_DIGEST_LEN_SHA384) {
-            error_setg(errp, "TDX: failed to decode mrconfigid");
+            error_setg(errp, "TDX 'mrconfigid' sha384 digest was %ld bytes, "
+                             "expected %d bytes", data_len,
+                             QCRYPTO_HASH_DIGEST_LEN_SHA384);
             return -1;
         }
         memcpy(init_vm->mrconfigid, data, data_len);
@@ -1045,7 +1047,9 @@ int tdx_pre_create_vcpu(CPUState *cpu, Error **errp)
             return -1;
         }
         if (data_len != QCRYPTO_HASH_DIGEST_LEN_SHA384) {
-            error_setg(errp, "TDX: failed to decode mrowner");
+            error_setg(errp, "TDX 'mrowner' sha384 digest was %ld bytes, "
+                             "expected %d bytes", data_len,
+                             QCRYPTO_HASH_DIGEST_LEN_SHA384);
             return -1;
         }
         memcpy(init_vm->mrowner, data, data_len);
@@ -1058,7 +1062,9 @@ int tdx_pre_create_vcpu(CPUState *cpu, Error **errp)
             return -1;
         }
         if (data_len != QCRYPTO_HASH_DIGEST_LEN_SHA384) {
-            error_setg(errp, "TDX: failed to decode mrownerconfig");
+            error_setg(errp, "TDX 'mrownerconfig' sha384 digest was %ld bytes, "
+                             "expected %d bytes", data_len,
+                             QCRYPTO_HASH_DIGEST_LEN_SHA384);
             return -1;
         }
         memcpy(init_vm->mrownerconfig, data, data_len);
-- 
2.49.0