vmwgfx: Fix display system init & close functions

Make sure we null the display private, make sure we catch and
handle vblank failing to init and don't call vblank_cleanup if
we haven't initialized the display system.

Signed-off-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c

@@ -380,29 +380,43 @@ int vmw_kms_init_legacy_display_system(struct vmw_private *dev_priv)
 	dev_priv->ldu_priv->last_num_active = 0;
 	dev_priv->ldu_priv->fb = NULL;
 
-	drm_mode_create_dirty_info_property(dev_priv->dev);
+	/* for old hardware without multimon only enable one display */
+	if (dev_priv->capabilities & SVGA_CAP_MULTIMON)
+		ret = drm_vblank_init(dev, VMWGFX_NUM_DISPLAY_UNITS);
+	else
+		ret = drm_vblank_init(dev, 1);
+	if (ret != 0)
+		goto err_free;
 
-	if (dev_priv->capabilities & SVGA_CAP_MULTIMON) {
+	ret = drm_mode_create_dirty_info_property(dev);
+	if (ret != 0)
+		goto err_vblank_cleanup;
+
+	if (dev_priv->capabilities & SVGA_CAP_MULTIMON)
 		for (i = 0; i < VMWGFX_NUM_DISPLAY_UNITS; ++i)
 			vmw_ldu_init(dev_priv, i);
-		ret = drm_vblank_init(dev, VMWGFX_NUM_DISPLAY_UNITS);
-	} else {
-		/* for old hardware without multimon only enable one display */
+	else
 		vmw_ldu_init(dev_priv, 0);
-		ret = drm_vblank_init(dev, 1);
-	}
 
+	return 0;
+
+err_vblank_cleanup:
+	drm_vblank_cleanup(dev);
+err_free:
+	kfree(dev_priv->ldu_priv);
+	dev_priv->ldu_priv = NULL;
 	return ret;
 }
 
 int vmw_kms_close_legacy_display_system(struct vmw_private *dev_priv)
 {
 	struct drm_device *dev = dev_priv->dev;
 
-	drm_vblank_cleanup(dev);
 	if (!dev_priv->ldu_priv)
 		return -ENOSYS;
 
+	drm_vblank_cleanup(dev);
+
 	BUG_ON(!list_empty(&dev_priv->ldu_priv->active));
 
 	kfree(dev_priv->ldu_priv);

drivers/gpu/drm/vmwgfx/vmwgfx_scrn.c

@@ -545,6 +545,7 @@ int vmw_kms_init_screen_object_display(struct vmw_private *dev_priv)
 	drm_vblank_cleanup(dev);
 err_free:
 	kfree(dev_priv->sou_priv);
+	dev_priv->sou_priv = NULL;
 err_no_mem:
 	return ret;
 }
@@ -553,10 +554,11 @@ int vmw_kms_close_screen_object_display(struct vmw_private *dev_priv)
 {
 	struct drm_device *dev = dev_priv->dev;
 
-	drm_vblank_cleanup(dev);
 	if (!dev_priv->sou_priv)
 		return -ENOSYS;
 
+	drm_vblank_cleanup(dev);
+
 	if (!list_empty(&dev_priv->sou_priv->active))
 		DRM_ERROR("Still have active outputs when unloading driver");