diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 1de16f21121aaacdabf64b3fd64a2750716baf64..12e2f8b8bf9c9b69928700398eb2485cd429f4a4 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -1157,7 +1157,9 @@ parse_device_mapping(struct drm_i915_private *dev_priv,
 		DRM_DEBUG_KMS("No general definition block is found, no devices defined.\n");
 		return;
 	}
-	if (bdb->version < 109) {
+	if (bdb->version < 106) {
+		expected_size = 22;
+	} else if (bdb->version < 109) {
 		expected_size = 27;
 	} else if (bdb->version < 195) {
 		BUILD_BUG_ON(sizeof(struct old_child_dev_config) != 33);