linux_5_4: remove

See https://endoflife.date/linux

Will be end of life on 2025-12-31 which is well within the timespan of
25.11.

nixos/doc/manual/release-notes/rl-2511.section.md

@@ -178,6 +178,8 @@
 
 - `hardware.amdgpu.amdvlk` and the `amdvlk` package have been removed, as they have been deprecated by AMD. These have been replaced with the RADV driver from Mesa, which is enabled by default.
 
+- Linux 5.4 and all its variants have been removed since mainline will reach its end of life within the support-span of 25.11.
+
 - The `services.polipo` module has been removed as `polipo` is unmaintained and archived upstream.
 
 - `virtualisation.lxd` has been removed due to lack of Nixpkgs maintenance. Users can migrate to `virtualisation.incus`, a fork of LXD, as a replacement. See [Incus migration documentation](https://linuxcontainers.org/incus/docs/main/howto/server_migrate_lxd/) for migration information.

nixos/tests/kernel-generic/default.nix

@@ -81,7 +81,6 @@ let
   kernels = patchedPkgs.linuxKernel.vanillaPackages // {
     inherit (patchedPkgs.linuxKernel.packages)
       linux_6_12_hardened
-      linux_rt_5_4
       linux_rt_5_10
       linux_rt_5_15
       linux_rt_6_1

pkgs/os-specific/linux/kernel/kernels-org.json

@@ -19,11 +19,6 @@
         "hash": "sha256:17wxs8i8vd5ivv99ra0sri3wmkw5c22wsaw8nf1xcvys2kmpa7hk",
         "lts": true
     },
-    "5.4": {
-        "version": "5.4.300",
-        "hash": "sha256:0nl1l689d4jq2l39v816yy7z5lzc5dvv8aqn85xlv4najc022jcr",
-        "lts": true
-    },
     "6.6": {
         "version": "6.6.113",
         "hash": "sha256:07n494cblmlfmn8l3kjalwlnb1f9xxxf8c31kkfr5lb1wk9cz58z",

pkgs/os-specific/linux/kernel/linux-rt-5.4.nix

@@ -1,60 +0,0 @@
-{
-  lib,
-  buildLinux,
-  fetchurl,
-  kernelPatches ? [ ],
-  structuredExtraConfig ? { },
-  extraMeta ? { },
-  argsOverride ? { },
-  ...
-}@args:
-
-let
-  version = "5.4.296-rt100"; # updated by ./update-rt.sh
-  branch = lib.versions.majorMinor version;
-  kversion = builtins.elemAt (lib.splitString "-" version) 0;
-in
-buildLinux (
-  args
-  // {
-    inherit version;
-    pname = "linux-rt";
-
-    src = fetchurl {
-      url = "mirror://kernel/linux/kernel/v5.x/linux-${kversion}.tar.xz";
-      sha256 = "0fm73yqzbzclh2achcj8arpg428d412k2wgmlfmyy6xzb1762qrx";
-    };
-
-    kernelPatches =
-      let
-        rt-patch = {
-          name = "rt";
-          patch = fetchurl {
-            url = "mirror://kernel/linux/kernel/projects/rt/${branch}/older/patch-${version}.patch.xz";
-            sha256 = "0ggmgkhmnvx4xxb3smfdcafqr9m3qdyc40xp3h7586p4n3wwpw9d";
-          };
-        };
-      in
-      [ rt-patch ] ++ kernelPatches;
-
-    structuredExtraConfig =
-      with lib.kernel;
-      {
-        PREEMPT_RT = yes;
-        # Fix error: unused option: PREEMPT_RT.
-        EXPERT = yes; # PREEMPT_RT depends on it (in kernel/Kconfig.preempt)
-        # Fix error: option not set correctly: PREEMPT_VOLUNTARY (wanted 'y', got 'n').
-        PREEMPT_VOLUNTARY = lib.mkForce no; # PREEMPT_RT deselects it.
-        # Fix error: unused option: RT_GROUP_SCHED.
-        RT_GROUP_SCHED = lib.mkForce (option no); # Removed by sched-disable-rt-group-sched-on-rt.patch.
-      }
-      // structuredExtraConfig;
-
-    isLTS = true;
-
-    extraMeta = extraMeta // {
-      inherit branch;
-    };
-  }
-  // argsOverride
-)

pkgs/top-level/linux-kernels.nix

@@ -116,22 +116,6 @@ in
           rpiVersion = 4;
         };
 
-        linux_5_4 = callPackage ../os-specific/linux/kernel/mainline.nix {
-          branch = "5.4";
-          kernelPatches = [
-            kernelPatches.bridge_stp_helper
-            kernelPatches.request_key_helper
-            kernelPatches.rtl8761b_support
-          ];
-        };
-
-        linux_rt_5_4 = callPackage ../os-specific/linux/kernel/linux-rt-5.4.nix {
-          kernelPatches = [
-            kernelPatches.bridge_stp_helper
-            kernelPatches.request_key_helper
-          ];
-        };
-
         linux_5_10 = callPackage ../os-specific/linux/kernel/mainline.nix {
           branch = "5.10";
           kernelPatches = [
@@ -285,6 +269,7 @@ in
         linux_latest_libre = throw "linux_latest_libre has been removed due to lack of maintenance";
 
         linux_4_19 = throw "linux 4.19 was removed because it will reach its end of life within 24.11";
+        linux_5_4 = throw "linux 5.4 was removed because it will reach its end of life within 25.11";
         linux_6_9 = throw "linux 6.9 was removed because it has reached its end of life upstream";
         linux_6_10 = throw "linux 6.10 was removed because it has reached its end of life upstream";
         linux_6_11 = throw "linux 6.11 was removed because it has reached its end of life upstream";
@@ -307,6 +292,8 @@ in
         linux_6_14_hardened = throw "linux 6.14 was removed because it has reached its end of life upstream";
         linux_6_15_hardened = throw "linux 6.15 was removed because it has reached its end of life upstream";
 
+        linux_rt_5_4 = throw "linux_rt 5.4 has been removed because it will reach its end of life within 25.11";
+
         linux_ham = throw "linux_ham has been removed in favour of the standard kernel packages";
       }
     )
@@ -722,7 +709,6 @@ in
 
   vanillaPackages = {
     # recurse to build modules for the kernels
-    linux_5_4 = recurseIntoAttrs (packagesFor kernels.linux_5_4);
     linux_5_10 = recurseIntoAttrs (packagesFor kernels.linux_5_10);
     linux_5_15 = recurseIntoAttrs (packagesFor kernels.linux_5_15);
     linux_6_1 = recurseIntoAttrs (packagesFor kernels.linux_6_1);
@@ -732,6 +718,7 @@ in
   }
   // lib.optionalAttrs config.allowAliases {
     linux_4_19 = throw "linux 4.19 was removed because it will reach its end of life within 24.11"; # Added 2024-09-21
+    linux_5_4 = throw "linux 5.4 was removed because it will reach its end of life within 25.11"; # Added 2025-10-22
     linux_6_9 = throw "linux 6.9 was removed because it reached its end of life upstream"; # Added 2024-08-02
     linux_6_10 = throw "linux 6.10 was removed because it reached its end of life upstream"; # Added 2024-10-23
     linux_6_11 = throw "linux 6.11 was removed because it reached its end of life upstream"; # Added 2025-03-23
@@ -743,11 +730,13 @@ in
 
   rtPackages = {
     # realtime kernel packages
-    linux_rt_5_4 = packagesFor kernels.linux_rt_5_4;
     linux_rt_5_10 = packagesFor kernels.linux_rt_5_10;
     linux_rt_5_15 = packagesFor kernels.linux_rt_5_15;
     linux_rt_6_1 = packagesFor kernels.linux_rt_6_1;
     linux_rt_6_6 = packagesFor kernels.linux_rt_6_6;
+  }
+  // lib.optionalAttrs config.allowAliases {
+    linux_rt_5_4 = throw "linux_rt 5.4 was removed because it will reach its end of life within 25.11"; # Added 2025-10-22
   };
 
   rpiPackages = {