nixpkgs/pkgs/os-specific/linux/kernel/generic.nix
Joachim Fasting 6eea9ac868
linux: add feature flag to indicate support for 32bit emulation
Motivated by the need to warn users trying to build configurations that depend
on being able to run 32bit apps on 64bit kernels.
2019-01-06 19:52:03 +01:00

142 lines
4.5 KiB
Nix

{ buildPackages
, ncurses
, callPackage
, perl
, bison ? null
, flex ? null
, stdenv
, # The kernel source tarball.
src
, # The kernel version.
version
, # Allows overriding the default defconfig
defconfig ? null
, # Legacy overrides to the intermediate kernel config, as string
extraConfig ? ""
, # kernel intermediate config overrides, as a set
structuredExtraConfig ? {}
, # The version number used for the module directory
modDirVersion ? version
, # An attribute set whose attributes express the availability of
# certain features in this kernel. E.g. `{iwlwifi = true;}'
# indicates a kernel that provides Intel wireless support. Used in
# NixOS to implement kernel-specific behaviour.
features ? {}
, # A list of patches to apply to the kernel. Each element of this list
# should be an attribute set {name, patch} where `name' is a
# symbolic name and `patch' is the actual patch. The patch may
# optionally be compressed with gzip or bzip2.
kernelPatches ? []
, ignoreConfigErrors ? stdenv.hostPlatform.platform.name != "pc" ||
stdenv.hostPlatform != stdenv.buildPlatform
, extraMeta ? {}
# easy overrides to stdenv.hostPlatform.platform members
, autoModules ? stdenv.hostPlatform.platform.kernelAutoModules
, preferBuiltin ? stdenv.hostPlatform.platform.kernelPreferBuiltin or false
, kernelArch ? stdenv.hostPlatform.platform.kernelArch
, mkValueOverride ? null
, ...
}:
assert stdenv.isLinux;
let
lib = stdenv.lib;
# Combine the `features' attribute sets of all the kernel patches.
kernelFeatures = lib.fold (x: y: (x.features or {}) // y) ({
iwlwifi = true;
efiBootStub = true;
needsCifsUtils = true;
netfilterRPFilter = true;
grsecurity = false;
xen_dom0 = false;
ia32Emulation = true;
} // features) kernelPatches;
intermediateNixConfig = import ./common-config.nix {
inherit stdenv version structuredExtraConfig mkValueOverride;
# append extraConfig for backwards compatibility but also means the user can't override the kernelExtraConfig part
extraConfig = extraConfig + lib.optionalString (stdenv.hostPlatform.platform ? kernelExtraConfig) stdenv.hostPlatform.platform.kernelExtraConfig;
features = kernelFeatures; # Ensure we know of all extra patches, etc.
};
kernelConfigFun = baseConfig:
let
configFromPatches =
map ({extraConfig ? "", ...}: extraConfig) kernelPatches;
in lib.concatStringsSep "\n" ([baseConfig] ++ configFromPatches);
configfile = stdenv.mkDerivation {
inherit ignoreConfigErrors autoModules preferBuiltin kernelArch;
name = "linux-config-${version}";
generateConfig = ./generate-config.pl;
kernelConfig = kernelConfigFun intermediateNixConfig;
passAsFile = [ "kernelConfig" ];
depsBuildBuild = [ buildPackages.stdenv.cc ];
nativeBuildInputs = [ perl ]
++ lib.optionals (stdenv.lib.versionAtLeast version "4.16") [ bison flex ];
platformName = stdenv.hostPlatform.platform.name;
# e.g. "defconfig"
kernelBaseConfig = if defconfig != null then defconfig else stdenv.hostPlatform.platform.kernelBaseConfig;
# e.g. "bzImage"
kernelTarget = stdenv.hostPlatform.platform.kernelTarget;
prePatch = kernel.prePatch + ''
# Patch kconfig to print "###" after every question so that
# generate-config.pl from the generic builder can answer them.
sed -e '/fflush(stdout);/i\printf("###");' -i scripts/kconfig/conf.c
'';
preUnpack = kernel.preUnpack or "";
inherit (kernel) src patches;
buildPhase = ''
export buildRoot="''${buildRoot:-build}"
# Get a basic config file for later refinement with $generateConfig.
make HOSTCC=${buildPackages.stdenv.cc.targetPrefix}gcc -C . O="$buildRoot" $kernelBaseConfig ARCH=$kernelArch
# Create the config file.
echo "generating kernel configuration..."
ln -s "$kernelConfigPath" "$buildRoot/kernel-config"
DEBUG=1 ARCH=$kernelArch KERNEL_CONFIG="$buildRoot/kernel-config" AUTO_MODULES=$autoModules \
PREFER_BUILTIN=$preferBuiltin BUILD_ROOT="$buildRoot" SRC=. perl -w $generateConfig
'';
installPhase = "mv $buildRoot/.config $out";
enableParallelBuilding = true;
};
kernel = (callPackage ./manual-config.nix {}) {
inherit version modDirVersion src kernelPatches stdenv extraMeta configfile;
config = { CONFIG_MODULES = "y"; CONFIG_FW_LOADER = "m"; };
};
passthru = {
features = kernelFeatures;
passthru = kernel.passthru // (removeAttrs passthru [ "passthru" ]);
};
in lib.extendDerivation true passthru kernel