From e07f4d6795413d98a2b871d5a8e03d6a9bd16e0f Mon Sep 17 00:00:00 2001
From: Tad Fisher <tadfisher@gmail.com>
Date: Thu, 29 Oct 2020 15:02:33 -0700
Subject: [PATCH] nixos/throttled: disable kernel msr warning

---
 nixos/modules/services/hardware/throttled.nix | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/nixos/modules/services/hardware/throttled.nix b/nixos/modules/services/hardware/throttled.nix
index 7617c4492d7c..1905eb565c6d 100644
--- a/nixos/modules/services/hardware/throttled.nix
+++ b/nixos/modules/services/hardware/throttled.nix
@@ -26,5 +26,11 @@ in {
       if cfg.extraConfig != ""
       then pkgs.writeText "lenovo_fix.conf" cfg.extraConfig
       else "${pkgs.throttled}/etc/lenovo_fix.conf";
+
+    # Kernel 5.9 spams warnings whenever userspace writes to CPU MSRs.
+    # See https://github.com/erpalma/throttled/issues/215
+    boot.kernelParams =
+      optional (versionAtLeast config.boot.kernelPackages.kernel.version "5.9")
+      "msr.allow_writes=on";
   };
 }