diff --git a/src/emu/stream.c b/src/emu/stream.c
index a589742..b723c43 100644
--- a/src/emu/stream.c
+++ b/src/emu/stream.c
@@ -113,6 +113,26 @@ load_obs(struct stream *stream, const char *path)
 	return 0;
 }
 
+static int
+check_version(JSON_Object *meta)
+{
+	JSON_Value *version_val = json_object_get_value(meta, "version");
+	if (version_val == NULL) {
+		err("missing attribute \"version\"");
+		return -1;
+	}
+
+	int version = (int) json_number(version_val);
+
+	if (version != OVNI_METADATA_VERSION) {
+		err("metadata version mismatch %d (expected %d)",
+				version, OVNI_METADATA_VERSION);
+		return -1;
+	}
+
+	return 0;
+}
+
 static JSON_Object *
 load_json(const char *path)
 {
@@ -129,6 +149,10 @@ load_json(const char *path)
 	}
 
 	/* TODO: Check version */
+	if (check_version(meta) != 0) {
+		err("check_version failed");
+		return NULL;
+	}
 
 	return meta;
 }
diff --git a/src/emu/thread.c b/src/emu/thread.c
index 16e7e0b..9534bb8 100644
--- a/src/emu/thread.c
+++ b/src/emu/thread.c
@@ -417,8 +417,10 @@ thread_load_metadata(struct thread *thread, struct stream *s)
 		return -1;
 	}
 
-	if (json_object_dotget_number(meta, "ovni.finished") != 1)
-		warn("thread didn't finish properly: %s", thread->id);
+	if (json_object_dotget_number(meta, "ovni.finished") != 1) {
+		err("missing ovni.finished: %s", s->relpath);
+		return -1;
+	}
 
 	thread->meta = meta;
 
diff --git a/test/emu/ovni/CMakeLists.txt b/test/emu/ovni/CMakeLists.txt
index e011ce2..3a44cd2 100644
--- a/test/emu/ovni/CMakeLists.txt
+++ b/test/emu/ovni/CMakeLists.txt
@@ -18,11 +18,11 @@ test_emu(no-cpus.c SHOULD_FAIL REGEX "loom .* has no physical CPUs")
 test_emu(sort-cpus-by-loom.c MP)
 test_emu(sort-cpus-by-rank.c MP)
 test_emu(tracedir-subdir.c MP DRIVER "tracedir-subdir.driver.sh")
-test_emu(empty-stream.c SHOULD_FAIL REGEX "model_ovni_finish: thread .* is not dead")
+test_emu(empty-stream.c SHOULD_FAIL REGEX "missing ovni.finished")
 test_emu(require-bad-version.c SHOULD_FAIL REGEX "unsupported ovni model version (want 666.66.6, have .*)")
 test_emu(require-compat.c REGEX "loading trace in compatibility mode")
 test_emu(require-repeated.c)
-test_emu(thread-crash.c SHOULD_FAIL REGEX "incomplete stream")
+test_emu(thread-crash.c SHOULD_FAIL REGEX "missing ovni.finished")
 test_emu(thread-free-isready.c)
 test_emu(flush-tmpdir.c MP DRIVER "flush-tmpdir.driver.sh")
 test_emu(tmpdir-metadata.c MP DRIVER "tmpdir-metadata.driver.sh")