diff --git a/src/signature.c b/src/signature.c
index 10465962..972bc5d0 100644
--- a/src/signature.c
+++ b/src/signature.c
@@ -2290,10 +2290,23 @@ static int p11prov_eddsa_set_ctx_params(void *ctx, const OSSL_PARAM params[])
 {
     P11PROV_SIG_CTX *sigctx = (P11PROV_SIG_CTX *)ctx;
     const OSSL_PARAM *p;
+    CK_ULONG size;
     int ret;
 
     P11PROV_debug("eddsa set ctx params (ctx=%p, params=%p)", sigctx, params);
 
+    size = p11prov_obj_get_key_bit_size(sigctx->key);
+    if (size != ED25519_BIT_SIZE && size != ED448_BIT_SIZE) {
+        P11PROV_raise(sigctx->provctx, CKR_KEY_TYPE_INCONSISTENT,
+                      "Invalid EdDSA key size %lu", size);
+        return RET_OSSL_ERR;
+    }
+
+    /* PKCS #11 parameters are mandatory for Ed448 key type anyway */
+    if (size == ED448_BIT_SIZE) {
+        sigctx->use_eddsa_params = CK_TRUE;
+    }
+
     if (params == NULL) {
         return RET_OSSL_OK;
     }
@@ -2302,7 +2315,6 @@ static int p11prov_eddsa_set_ctx_params(void *ctx, const OSSL_PARAM params[])
     if (p) {
         const char *instance = NULL;
         bool matched = false;
-        CK_ULONG size;
 
         ret = OSSL_PARAM_get_utf8_string_ptr(p, &instance);
         if (ret != RET_OSSL_OK) {
@@ -2310,12 +2322,6 @@ static int p11prov_eddsa_set_ctx_params(void *ctx, const OSSL_PARAM params[])
         }
         P11PROV_debug("Set OSSL_SIGNATURE_PARAM_INSTANCE to %s", instance);
 
-        size = p11prov_obj_get_key_bit_size(sigctx->key);
-        if (size != ED25519_BIT_SIZE && size != ED448_BIT_SIZE) {
-            P11PROV_raise(sigctx->provctx, CKR_KEY_TYPE_INCONSISTENT,
-                          "Invalid EdDSA key size %lu", size);
-            return RET_OSSL_ERR;
-        }
         if (size == ED25519_BIT_SIZE) {
             if (OPENSSL_strcasecmp(instance, "Ed25519") == 0) {
                 matched = true;
@@ -2359,6 +2365,7 @@ static int p11prov_eddsa_set_ctx_params(void *ctx, const OSSL_PARAM params[])
             return ret;
         }
         sigctx->eddsa_params.ulContextDataLen = datalen;
+        sigctx->use_eddsa_params = CK_TRUE;
     }
 
     return RET_OSSL_OK;