From 9bfa21368b2af1c0d05453a1adf9000538c402d7 Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Fri, 28 Aug 2026 12:20:52 -0400
Subject: [PATCH] Update to Linux 7.2.

This is to pull in the drivers for the mt7927 wireless chipset in my desktop. Normally, I would keep the rest of my machines on LTS but since Linux 7 significantly changed the kernel preemption, maintaining two configs would be more trouble than it is worth.
---
 nix/configuration/roles/kernel/default.nix | 35 +++++-----------------
 1 file changed, 8 insertions(+), 27 deletions(-)

diff --git a/nix/configuration/roles/kernel/default.nix b/nix/configuration/roles/kernel/default.nix
index 58493fc..6686b8e 100644
--- a/nix/configuration/roles/kernel/default.nix
+++ b/nix/configuration/roles/kernel/default.nix
@@ -14,30 +14,12 @@ let
     full = {
       PREEMPT_DYNAMIC = yes;
       PREEMPT = yes;
-      PREEMPT_VOLUNTARY = lib.mkForce no;
       PREEMPT_LAZY = lib.mkForce no;
-      PREEMPT_NONE = no;
     };
     lazy = {
       PREEMPT_DYNAMIC = yes;
       PREEMPT = no;
-      PREEMPT_VOLUNTARY = lib.mkForce no;
       PREEMPT_LAZY = yes;
-      PREEMPT_NONE = no;
-    };
-    voluntary = {
-      PREEMPT_DYNAMIC = no;
-      PREEMPT = no;
-      PREEMPT_VOLUNTARY = yes;
-      PREEMPT_LAZY = lib.mkForce no;
-      PREEMPT_NONE = no;
-    };
-    none = {
-      PREEMPT_DYNAMIC = no;
-      PREEMPT = no;
-      PREEMPT_VOLUNTARY = lib.mkForce no;
-      PREEMPT_LAZY = lib.mkForce no;
-      PREEMPT_NONE = yes;
     };
   };
   tick_hz =
@@ -99,16 +81,14 @@ let
       TRANSPARENT_HUGEPAGE_MADVISE = yes;
     };
   };
-  common_config =
-    with lib.kernel;
-    {
-      # Google's BBRv3 TCP congestion Control
-      TCP_CONG_BBR = yes;
-      DEFAULT_BBR = yes;
-    };
+  common_config = with lib.kernel; {
+    # Google's BBRv3 TCP congestion Control
+    TCP_CONG_BBR = yes;
+    DEFAULT_BBR = yes;
+  };
   flavors = {
     server = lib.mkMerge [
-      preemption_type.none
+      preemption_type.lazy
       tick_hz."300"
       performance_governor.default
       tick_rate.tickless
@@ -142,7 +122,8 @@ in
 
     kernel.version = lib.mkOption {
       type = lib.types.str;
-      default = "linux"; # LTS
+      # default = "linux"; # LTS
+      default = "linux_7_2"; # LTS
       example = "linux_6_18";
       description = "What version of the kernl should we use.";
     };