diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 59d6b9bf204bbd2d76b8440b3f7d435def394fe7..892ff9f959754263eb318da91347cbfffcc25ae7 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -1544,10 +1544,10 @@ int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
 	if (!fb_helper->fb)
 		return 0;
 
-	drm_modeset_lock_all(dev);
+	mutex_lock(&fb_helper->dev->mode_config.mutex);
 	if (!drm_fb_helper_is_bound(fb_helper)) {
 		fb_helper->delayed_hotplug = true;
-		drm_modeset_unlock_all(dev);
+		mutex_unlock(&fb_helper->dev->mode_config.mutex);
 		return 0;
 	}
 	DRM_DEBUG_KMS("\n");
@@ -1558,9 +1558,11 @@ int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
 
 	count = drm_fb_helper_probe_connector_modes(fb_helper, max_width,
 						    max_height);
+	mutex_unlock(&fb_helper->dev->mode_config.mutex);
+
+	drm_modeset_lock_all(dev);
 	drm_setup_crtcs(fb_helper);
 	drm_modeset_unlock_all(dev);
-
 	drm_fb_helper_set_par(fb_helper->fbdev);
 
 	return 0;
diff --git a/drivers/gpu/drm/udl/udl_connector.c b/drivers/gpu/drm/udl/udl_connector.c
index fe5cdbcf263605b7b5ec853b4d5f354f7c754b13..b44d548c56f8e43a3e14878622c8f8ed3507bf35 100644
--- a/drivers/gpu/drm/udl/udl_connector.c
+++ b/drivers/gpu/drm/udl/udl_connector.c
@@ -61,6 +61,10 @@ static int udl_get_modes(struct drm_connector *connector)
 	int ret;
 
 	edid = (struct edid *)udl_get_edid(udl);
+	if (!edid) {
+		drm_mode_connector_update_edid_property(connector, NULL);
+		return 0;
+	}
 
 	/*
 	 * We only read the main block, but if the monitor reports extension