diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 33d877c65ced6a3c138af9ab47c824038410be0b..8328e7059205d266a456710613628c64b097f787 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -4105,7 +4105,7 @@ drm_property_create_blob(struct drm_device *dev, size_t length,
 	struct drm_property_blob *blob;
 	int ret;
 
-	if (!length)
+	if (!length || length > ULONG_MAX - sizeof(struct drm_property_blob))
 		return ERR_PTR(-EINVAL);
 
 	blob = kzalloc(sizeof(struct drm_property_blob)+length, GFP_KERNEL);
@@ -4454,7 +4454,7 @@ int drm_mode_createblob_ioctl(struct drm_device *dev,
 	 * not associated with any file_priv. */
 	mutex_lock(&dev->mode_config.blob_lock);
 	out_resp->blob_id = blob->base.id;
-	list_add_tail(&file_priv->blobs, &blob->head_file);
+	list_add_tail(&blob->head_file, &file_priv->blobs);
 	mutex_unlock(&dev->mode_config.blob_lock);
 
 	return 0;
diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c
index 65adb9c723772d9f0011573d320182823b18d37a..bb292143997ee8ccce3e6e6898edba2a5eeb12b6 100644
--- a/drivers/gpu/drm/radeon/atombios_encoders.c
+++ b/drivers/gpu/drm/radeon/atombios_encoders.c
@@ -237,6 +237,7 @@ void radeon_atom_backlight_init(struct radeon_encoder *radeon_encoder,
 	backlight_update_status(bd);
 
 	DRM_INFO("radeon atom DIG backlight initialized\n");
+	rdev->mode_info.bl_encoder = radeon_encoder;
 
 	return;
 
@@ -1624,9 +1625,14 @@ radeon_atom_encoder_dpms_avivo(struct drm_encoder *encoder, int mode)
 		} else
 			atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
 		if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)) {
-			struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
+			if (rdev->mode_info.bl_encoder) {
+				struct radeon_encoder_atom_dig *dig = radeon_encoder->enc_priv;
 
-			atombios_set_backlight_level(radeon_encoder, dig->backlight_level);
+				atombios_set_backlight_level(radeon_encoder, dig->backlight_level);
+			} else {
+				args.ucAction = ATOM_LCD_BLON;
+				atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
+			}
 		}
 		break;
 	case DRM_MODE_DPMS_STANDBY:
@@ -1706,8 +1712,13 @@ radeon_atom_encoder_dpms_dig(struct drm_encoder *encoder, int mode)
 			if (ASIC_IS_DCE4(rdev))
 				atombios_dig_encoder_setup(encoder, ATOM_ENCODER_CMD_DP_VIDEO_ON, 0);
 		}
-		if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT))
-			atombios_set_backlight_level(radeon_encoder, dig->backlight_level);
+		if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)) {
+			if (rdev->mode_info.bl_encoder)
+				atombios_set_backlight_level(radeon_encoder, dig->backlight_level);
+			else
+				atombios_dig_transmitter_setup(encoder,
+							       ATOM_TRANSMITTER_ACTION_LCD_BLON, 0, 0);
+		}
 		if (ext_encoder)
 			atombios_external_encoder_setup(encoder, ext_encoder, ATOM_ENABLE);
 		break;
diff --git a/drivers/gpu/drm/radeon/radeon_encoders.c b/drivers/gpu/drm/radeon/radeon_encoders.c
index ef99917f000d96a7dcf3fc88f089bdf08e0afc28..c6ee80216cf4a71f510bf239fc4fdf6f67235f48 100644
--- a/drivers/gpu/drm/radeon/radeon_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_encoders.c
@@ -194,7 +194,6 @@ static void radeon_encoder_add_backlight(struct radeon_encoder *radeon_encoder,
 			radeon_atom_backlight_init(radeon_encoder, connector);
 		else
 			radeon_legacy_backlight_init(radeon_encoder, connector);
-		rdev->mode_info.bl_encoder = radeon_encoder;
 	}
 }
 
diff --git a/drivers/gpu/drm/radeon/radeon_legacy_encoders.c b/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
index 45715307db7177a9af7393a697d255c8ed277344..30de43366eae806d0afd45192ce9da032c08490c 100644
--- a/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
@@ -441,6 +441,7 @@ void radeon_legacy_backlight_init(struct radeon_encoder *radeon_encoder,
 	backlight_update_status(bd);
 
 	DRM_INFO("radeon legacy LVDS backlight initialized\n");
+	rdev->mode_info.bl_encoder = radeon_encoder;
 
 	return;