From 500d61560fb76b46db017109ff5b9ddc50e02434 Mon Sep 17 00:00:00 2001
From: Michael Raskin <7c6f434c@mail.ru>
Date: Thu, 7 Mar 2019 13:38:05 +0100
Subject: [PATCH] Release notes: switch to modesetting: mention backlight
 problem

---
 nixos/doc/manual/release-notes/rl-1903.xml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/nixos/doc/manual/release-notes/rl-1903.xml b/nixos/doc/manual/release-notes/rl-1903.xml
index 18d32b59584b..e58ce49c79bd 100644
--- a/nixos/doc/manual/release-notes/rl-1903.xml
+++ b/nixos/doc/manual/release-notes/rl-1903.xml
@@ -666,6 +666,10 @@
         Some OpenCL and VA-API applications might also break
         (Beignet seems to provide OpenCL support with
         <literal>modesetting</literal> driver, too).
+        Kernel mode setting API does not support backlight control,
+        so <literal>xbacklight</literal> tool will not work;
+        backlight level can be controlled directly via <literal>/sys/</literal>
+        or with <literal>brightnessctl</literal>.
         Users who need this functionality more than multi-output XRandR are advised
         to add `intel` to `videoDrivers` and report an issue (or provide additional
         details in an existing one)