Merge pull request #107703 from Atemu/kernel-use-zstd

kernel: use zstd

nixos/modules/system/boot/stage-1.nix

@@ -513,7 +513,12 @@ in
     };
 
     boot.initrd.compressor = mkOption {
-      default = "gzip";
+      default = (
+        if lib.versionAtLeast config.boot.kernelPackages.kernel.version "5.9"
+        then "zstd"
+        else "gzip"
+      );
+      defaultText = "zstd if the kernel supports it (5.9+), gzip if not.";
       type = types.unspecified; # We don't have a function type...
       description = ''
         The compressor to use on the initrd image. May be any of:

pkgs/os-specific/linux/kernel/common-config.nix

@@ -654,7 +654,10 @@ let
 
       MODULE_COMPRESS    = yes;
       MODULE_COMPRESS_XZ = yes;
-      KERNEL_XZ          = yes;
+
+      # use zstd for kernel compression if newer than 5.9, else xz.
+      KERNEL_XZ          = whenOlder "5.9" yes;
+      KERNEL_ZSTD        = whenAtLeast "5.9" yes;
 
       SYSVIPC            = yes;  # System-V IPC
 

pkgs/os-specific/linux/kernel/manual-config.nix

@@ -1,5 +1,5 @@
 { buildPackages, runCommand, nettools, bc, bison, flex, perl, rsync, gmp, libmpc, mpfr, openssl
-, libelf, cpio, elfutils
+, libelf, cpio, elfutils, zstd, gawk
 , writeTextFile
 }:
 
@@ -120,7 +120,7 @@ let
         # See also https://kernelnewbies.org/BuildId
         sed -i Makefile -e 's|--build-id|--build-id=none|'
 
-        sed -i scripts/ld-version.sh -e "s|/usr/bin/awk|${buildPackages.gawk}/bin/awk|"
+        patchShebangs scripts/ld-version.sh
       '';
 
       postPatch = ''
@@ -306,7 +306,7 @@ stdenv.mkDerivation ((drvAttrs config stdenv.hostPlatform.platform kernelPatches
   enableParallelBuilding = true;
 
   depsBuildBuild = [ buildPackages.stdenv.cc ];
-  nativeBuildInputs = [ perl bc nettools openssl rsync gmp libmpc mpfr ]
+  nativeBuildInputs = [ perl bc nettools openssl rsync gmp libmpc mpfr gawk zstd ]
       ++ optional  (stdenv.hostPlatform.platform.kernelTarget == "uImage") buildPackages.ubootTools
       ++ optional  (stdenv.lib.versionAtLeast version "4.14" && stdenv.lib.versionOlder version "5.8") libelf
       # Removed util-linuxMinimal since it should not be a dependency.