nixpkgs/pkgs/os-specific/linux/kernel/manual-config.nix
Alyssa Ross f521f46133 linuxManualConfig: get rid of drvAttrs
This is an attempt to make linuxManualConfig look a lot more like a
normal package.  Previously, about half the attributes passed to
mkDerivation come from calling a "drvAttrs" function, which just
served to alias some variables through function parameters.  There
wasn't really a system for which attributes came from drvAttrs, and
which did not.

I've also made a few other minor changes, like re-ordering attributes
to be more idiomatic, and using variables that were moved out of
drvAttrs in the definitions of attributes that weren't in drvAttrs
before.  I've limited my changes here to what I can confidently do
without causing any rebuilds.
2023-04-03 00:14:36 +00:00

414 lines
15 KiB
Nix

{ lib, stdenv, buildPackages, runCommand, nettools, bc, bison, flex, perl, rsync, gmp, libmpc, mpfr, openssl
, libelf, cpio, elfutils, zstd, python3Minimal, zlib, pahole
, fetchpatch
}:
let
lib_ = lib;
stdenv_ = stdenv;
readConfig = configfile: import (runCommand "config.nix" {} ''
echo "{" > "$out"
while IFS='=' read key val; do
[ "x''${key#CONFIG_}" != "x$key" ] || continue
no_firstquote="''${val#\"}";
echo ' "'"$key"'" = "'"''${no_firstquote%\"}"'";' >> "$out"
done < "${configfile}"
echo "}" >> $out
'').outPath;
in lib.makeOverridable ({
# The kernel version
version,
# Position of the Linux build expression
pos ? null,
# Additional kernel make flags
extraMakeFlags ? [],
# The name of the kernel module directory
# Needs to be X.Y.Z[-extra], so pad with zeros if needed.
modDirVersion ? lib.versions.pad 3 version,
# The kernel source (tarball, git checkout, etc.)
src,
# a list of { name=..., patch=..., extraConfig=...} patches
kernelPatches ? [],
# The kernel .config file
configfile,
# Manually specified nixexpr representing the config
# If unspecified, this will be autodetected from the .config
config ? lib.optionalAttrs allowImportFromDerivation (readConfig configfile),
# Custom seed used for CONFIG_GCC_PLUGIN_RANDSTRUCT if enabled. This is
# automatically extended with extra per-version and per-config values.
randstructSeed ? "",
# Extra meta attributes
extraMeta ? {},
# for module compatibility
isZen ? false,
isLibre ? false,
isHardened ? false,
# Whether to utilize the controversial import-from-derivation feature to parse the config
allowImportFromDerivation ? false,
# ignored
features ? null, lib ? lib_, stdenv ? stdenv_,
}:
let
config_ = config;
in
let
inherit (lib)
hasAttr getAttr optional optionals optionalString optionalAttrs maintainers platforms;
# Dependencies that are required to build kernel modules
moduleBuildDependencies = [
pahole
perl
libelf
# module makefiles often run uname commands to find out the kernel version
(buildPackages.deterministic-uname.override { inherit modDirVersion; })
] ++ optional (lib.versionAtLeast version "5.13") zstd;
config = let attrName = attr: "CONFIG_" + attr; in {
isSet = attr: hasAttr (attrName attr) config;
getValue = attr: if config.isSet attr then getAttr (attrName attr) config else null;
isYes = attr: (config.getValue attr) == "y";
isNo = attr: (config.getValue attr) == "n";
isModule = attr: (config.getValue attr) == "m";
isEnabled = attr: (config.isModule attr) || (config.isYes attr);
isDisabled = attr: (!(config.isSet attr)) || (config.isNo attr);
} // config_;
isModular = config.isYes "MODULES";
kernelConf = stdenv.hostPlatform.linux-kernel;
buildDTBs = kernelConf.DTB or false;
in
assert lib.versionOlder version "5.8" -> libelf != null;
assert lib.versionAtLeast version "5.8" -> elfutils != null;
stdenv.mkDerivation ({
pname = "linux";
inherit version src;
depsBuildBuild = [ buildPackages.stdenv.cc ];
nativeBuildInputs = [ perl bc nettools openssl rsync gmp libmpc mpfr zstd python3Minimal ]
++ optional (kernelConf.target == "uImage") buildPackages.ubootTools
++ optional (lib.versionOlder version "5.8") libelf
++ optionals (lib.versionAtLeast version "4.16") [ bison flex ]
++ optionals (lib.versionAtLeast version "5.2") [ cpio pahole zlib ]
++ optional (lib.versionAtLeast version "5.8") elfutils
;
patches =
map (p: p.patch) kernelPatches
# Required for deterministic builds along with some postPatch magic.
++ optional (lib.versionOlder version "5.19") ./randstruct-provide-seed.patch
++ optional (lib.versionAtLeast version "5.19") ./randstruct-provide-seed-5.19.patch
# Linux 5.12 marked certain PowerPC-only symbols as GPL, which breaks
# OpenZFS; this was fixed in Linux 5.19 so we backport the fix
# https://github.com/openzfs/zfs/pull/13367
++ optional (lib.versionAtLeast version "5.12" &&
lib.versionOlder version "5.19" &&
stdenv.hostPlatform.isPower)
(fetchpatch {
url = "https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/patch/?id=d9e5c3e9e75162f845880535957b7fd0b4637d23";
hash = "sha256-bBOyJcP6jUvozFJU0SPTOf3cmnTQ6ZZ4PlHjiniHXLU=";
});
preUnpack = ''
# The same preUnpack is used to build the configfile,
# which does not have $dev.
if [ -n "$dev" ]; then
mkdir -p $dev/lib/modules/${modDirVersion}
cd $dev/lib/modules/${modDirVersion}
fi
'';
postUnpack = ''
mv -Tv "$sourceRoot" source 2>/dev/null || :
export sourceRoot=$PWD/source
'';
postPatch = ''
sed -i Makefile -e 's|= depmod|= ${buildPackages.kmod}/bin/depmod|'
# fixup for pre-5.4 kernels using the $(cd $foo && /bin/pwd) pattern
# FIXME: remove when no longer needed
substituteInPlace Makefile tools/scripts/Makefile.include --replace /bin/pwd pwd
# Don't include a (random) NT_GNU_BUILD_ID, to make the build more deterministic.
# This way kernels can be bit-by-bit reproducible depending on settings
# (e.g. MODULE_SIG and SECURITY_LOCKDOWN_LSM need to be disabled).
# See also https://kernelnewbies.org/BuildId
sed -i Makefile -e 's|--build-id=[^ ]*|--build-id=none|'
# Some linux-hardened patches now remove certain files in the scripts directory, so the file may not exist.
[[ -f scripts/ld-version.sh ]] && patchShebangs scripts/ld-version.sh
# Set randstruct seed to a deterministic but diversified value. Note:
# we could have instead patched gen-random-seed.sh to take input from
# the buildFlags, but that would require also patching the kernel's
# toplevel Makefile to add a variable export. This would be likely to
# cause future patch conflicts.
for file in scripts/gen-randstruct-seed.sh scripts/gcc-plugins/gen-random-seed.sh; do
if [ -f "$file" ]; then
substituteInPlace "$file" \
--replace NIXOS_RANDSTRUCT_SEED \
$(echo ${randstructSeed}${src} ${placeholder "configfile"} | sha256sum | cut -d ' ' -f 1 | tr -d '\n')
break
fi
done
patchShebangs scripts
# also patch arch-specific install scripts
for i in $(find arch -name install.sh); do
patchShebangs "$i"
done
'';
configurePhase = ''
runHook preConfigure
export buildRoot=$(mktemp -d)
echo "manual-config configurePhase buildRoot=$buildRoot pwd=$PWD"
if [ -f "$buildRoot/.config" ]; then
echo "Could not link $buildRoot/.config : file exists"
exit 1
fi
ln -sv ${configfile} $buildRoot/.config
# reads the existing .config file and prompts the user for options in
# the current kernel source that are not found in the file.
make $makeFlags "''${makeFlagsArray[@]}" oldconfig
runHook postConfigure
make $makeFlags "''${makeFlagsArray[@]}" prepare
actualModDirVersion="$(cat $buildRoot/include/config/kernel.release)"
if [ "$actualModDirVersion" != "${modDirVersion}" ]; then
echo "Error: modDirVersion ${modDirVersion} specified in the Nix expression is wrong, it should be: $actualModDirVersion"
exit 1
fi
buildFlagsArray+=("KBUILD_BUILD_TIMESTAMP=$(date -u -d @$SOURCE_DATE_EPOCH)")
cd $buildRoot
'';
hardeningDisable = [ "bindnow" "format" "fortify" "stackprotector" "pic" "pie" ];
# Absolute paths for compilers avoid any PATH-clobbering issues.
makeFlags = [
"O=$(buildRoot)"
"CC=${stdenv.cc}/bin/${stdenv.cc.targetPrefix}cc"
"HOSTCC=${buildPackages.stdenv.cc}/bin/${buildPackages.stdenv.cc.targetPrefix}cc"
"HOSTLD=${buildPackages.stdenv.cc.bintools}/bin/${buildPackages.stdenv.cc.targetPrefix}ld"
"ARCH=${stdenv.hostPlatform.linuxArch}"
] ++ lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) [
"CROSS_COMPILE=${stdenv.cc.targetPrefix}"
] ++ (kernelConf.makeFlags or [])
++ extraMakeFlags;
karch = stdenv.hostPlatform.linuxArch;
buildFlags = [
"DTC_FLAGS=-@"
"KBUILD_BUILD_VERSION=1-NixOS"
# Set by default in the kernel since a73619a845d5,
# replicated here to apply to older versions.
# Makes __FILE__ relative to the build directory.
"KCPPFLAGS=-fmacro-prefix-map=$(sourceRoot)/="
] ++ extraMakeFlags;
installFlags = [
"INSTALL_PATH=$(out)"
] ++ (optional isModular "INSTALL_MOD_PATH=$(out)")
++ optionals buildDTBs ["dtbs_install" "INSTALL_DTBS_PATH=$(out)/dtbs"];
preInstall = let
# All we really need to do here is copy the final image and System.map to $out,
# and use the kernel's modules_install, firmware_install, dtbs_install, etc. targets
# for the rest. Easy, right?
#
# Unfortunately for us, the obvious way of getting the built image path,
# make -s image_name, does not work correctly, because some architectures
# (*cough* aarch64 *cough*) change KBUILD_IMAGE on the fly in their install targets,
# so we end up attempting to install the thing we didn't actually build.
#
# Thankfully, there's a way out that doesn't involve just hardcoding everything.
#
# The kernel has an install target, which runs a pretty simple shell script
# (located at scripts/install.sh or arch/$arch/boot/install.sh, depending on
# which kernel version you're looking at) that tries to do something sensible.
#
# (it would be great to hijack this script immediately, as it has all the
# information we need passed to it and we don't need it to try and be smart,
# but unfortunately, the exact location of the scripts differs between kernel
# versions, and they're seemingly not considered to be public API at all)
#
# One of the ways it tries to discover what "something sensible" actually is
# is by delegating to what's supposed to be a user-provided install script
# located at ~/bin/installkernel.
#
# (the other options are:
# - a distribution-specific script at /sbin/installkernel,
# which we can't really create in the sandbox easily
# - an architecture-specific script at arch/$arch/boot/install.sh,
# which attempts to guess _something_ and usually guesses very wrong)
#
# More specifically, the install script exec's into ~/bin/installkernel, if one
# exists, with the following arguments:
#
# $1: $KERNELRELEASE - full kernel version string
# $2: $KBUILD_IMAGE - the final image path
# $3: System.map - path to System.map file, seemingly hardcoded everywhere
# $4: $INSTALL_PATH - path to the destination directory as specified in installFlags
#
# $2 is exactly what we want, so hijack the script and use the knowledge given to it
# by the makefile overlords for our own nefarious ends.
#
# Note that the makefiles specifically look in ~/bin/installkernel, and
# writeShellScriptBin writes the script to <store path>/bin/installkernel,
# so HOME needs to be set to just the store path.
#
# FIXME: figure out a less roundabout way of doing this.
installkernel = buildPackages.writeShellScriptBin "installkernel" ''
cp -av $2 $4
cp -av $3 $4
'';
in ''
installFlagsArray+=("-j$NIX_BUILD_CORES")
export HOME=${installkernel}
'';
# Some image types need special install targets (e.g. uImage is installed with make uinstall)
installTargets = [
(kernelConf.installTarget or (
/**/ if kernelConf.target == "uImage" then "uinstall"
else if kernelConf.target == "zImage" || kernelConf.target == "Image.gz" then "zinstall"
else "install"))
];
postInstall = optionalString isModular ''
if [ -z "''${dontStrip-}" ]; then
installFlagsArray+=("INSTALL_MOD_STRIP=1")
fi
make modules_install $makeFlags "''${makeFlagsArray[@]}" \
$installFlags "''${installFlagsArray[@]}"
unlink $out/lib/modules/${modDirVersion}/build
unlink $out/lib/modules/${modDirVersion}/source
mkdir $dev/lib/modules/${modDirVersion}/build
cd $dev/lib/modules/${modDirVersion}/source
cp $buildRoot/{.config,Module.symvers} $dev/lib/modules/${modDirVersion}/build
make modules_prepare $makeFlags "''${makeFlagsArray[@]}" O=$dev/lib/modules/${modDirVersion}/build
# For reproducibility, removes accidental leftovers from a `cc1` call
# from a `try-run` call from the Makefile
rm -f $dev/lib/modules/${modDirVersion}/build/.[0-9]*.d
# Keep some extra files
for f in arch/powerpc/lib/crtsavres.o arch/arm64/kernel/ftrace-mod.o \
scripts/gdb/linux vmlinux vmlinux-gdb.py
do
if [ -e "$buildRoot/$f" ]; then
mkdir -p "$(dirname "$dev/lib/modules/${modDirVersion}/build/$f")"
cp -HR $buildRoot/$f $dev/lib/modules/${modDirVersion}/build/$f
fi
done
ln -s $dev/lib/modules/${modDirVersion}/build/vmlinux $dev
# !!! No documentation on how much of the source tree must be kept
# If/when kernel builds fail due to missing files, you can add
# them here. Note that we may see packages requiring headers
# from drivers/ in the future; it adds 50M to keep all of its
# headers on 3.10 though.
chmod u+w -R ..
arch=$(cd $dev/lib/modules/${modDirVersion}/build/arch; ls)
# Remove unused arches
for d in $(cd arch/; ls); do
if [ "$d" = "$arch" ]; then continue; fi
if [ "$arch" = arm64 ] && [ "$d" = arm ]; then continue; fi
rm -rf arch/$d
done
# Remove all driver-specific code (50M of which is headers)
rm -fR drivers
# Keep all headers
find . -type f -name '*.h' -print0 | xargs -0 -r chmod u-w
# Keep linker scripts (they are required for out-of-tree modules on aarch64)
find . -type f -name '*.lds' -print0 | xargs -0 -r chmod u-w
# Keep root and arch-specific Makefiles
chmod u-w Makefile arch/"$arch"/Makefile*
# Keep whole scripts dir
chmod u-w -R scripts
# Delete everything not kept
find . -type f -perm -u=w -print0 | xargs -0 -r rm
# Delete empty directories
find -empty -type d -delete
# Remove reference to kmod
sed -i Makefile -e 's|= ${buildPackages.kmod}/bin/depmod|= depmod|'
'';
preFixup = ''
# Don't strip $dev/lib/modules/*/vmlinux
stripDebugList="$(cd $dev && echo lib/modules/*/build/*/)"
'';
enableParallelBuilding = true;
passthru = rec {
inherit version modDirVersion config kernelPatches configfile
moduleBuildDependencies stdenv;
inherit isZen isHardened isLibre;
isXen = lib.warn "The isXen attribute is deprecated. All Nixpkgs kernels that support it now have Xen enabled." true;
baseVersion = lib.head (lib.splitString "-rc" version);
kernelOlder = lib.versionOlder baseVersion;
kernelAtLeast = lib.versionAtLeast baseVersion;
};
requiredSystemFeatures = [ "big-parallel" ];
meta = {
description =
"The Linux kernel" +
(if kernelPatches == [] then "" else
" (with patches: "
+ lib.concatStringsSep ", " (map (x: x.name) kernelPatches)
+ ")");
license = lib.licenses.gpl2Only;
homepage = "https://www.kernel.org/";
maintainers = lib.teams.linux-kernel.members ++ [
maintainers.thoughtpolice
];
platforms = platforms.linux;
timeout = 14400; # 4 hours
} // extraMeta;
} // optionalAttrs (pos != null) {
inherit pos;
} // optionalAttrs isModular {
outputs = [ "out" "dev" ];
}))