From f521f4613355f8628fe378dad4c41d3fd8886966 Mon Sep 17 00:00:00 2001 From: Alyssa Ross Date: Tue, 21 Mar 2023 21:56:06 +0000 Subject: [PATCH] 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. --- .../linux/kernel/manual-config.nix | 614 +++++++++--------- 1 file changed, 309 insertions(+), 305 deletions(-) diff --git a/pkgs/os-specific/linux/kernel/manual-config.nix b/pkgs/os-specific/linux/kernel/manual-config.nix index 46407eccf057..656ca7086311 100644 --- a/pkgs/os-specific/linux/kernel/manual-config.nix +++ b/pkgs/os-specific/linux/kernel/manual-config.nix @@ -52,6 +52,10 @@ in lib.makeOverridable ({ features ? null, lib ? lib_, stdenv ? stdenv_, }: +let + config_ = config; +in + let inherit (lib) hasAttr getAttr optional optionals optionalString optionalAttrs maintainers platforms; @@ -65,333 +69,143 @@ let (buildPackages.deterministic-uname.override { inherit modDirVersion; }) ] ++ optional (lib.versionAtLeast version "5.13") zstd; - drvAttrs = config_: kernelConf: kernelPatches: configfile: - let - config = let attrName = attr: "CONFIG_" + attr; in { - isSet = attr: hasAttr (attrName attr) config; + 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; + getValue = attr: if config.isSet attr then getAttr (attrName attr) config else null; - isYes = attr: (config.getValue attr) == "y"; + isYes = attr: (config.getValue attr) == "y"; - isNo = attr: (config.getValue attr) == "n"; + isNo = attr: (config.getValue attr) == "n"; - isModule = attr: (config.getValue attr) == "m"; + isModule = attr: (config.getValue attr) == "m"; - isEnabled = attr: (config.isModule attr) || (config.isYes attr); + isEnabled = attr: (config.isModule attr) || (config.isYes attr); - isDisabled = attr: (!(config.isSet attr)) || (config.isNo attr); - } // config_; + isDisabled = attr: (!(config.isSet attr)) || (config.isNo attr); + } // config_; - isModular = config.isYes "MODULES"; + isModular = config.isYes "MODULES"; - buildDTBs = kernelConf.DTB or false; + kernelConf = stdenv.hostPlatform.linux-kernel; - in (optionalAttrs isModular { outputs = [ "out" "dev" ]; }) // { - 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; - }; - - inherit src; - - 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 $buildRoot - ''; - - buildFlags = [ - "DTC_FLAGS=-@" - "KBUILD_BUILD_VERSION=1-NixOS" - - # Set by default in the kernel since a73619a845d5, - # replicated here to apply to older versions. - # Makes __FILE__ relative to the build directory. - "KCPPFLAGS=-fmacro-prefix-map=$(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 /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/*/)" - ''; - - 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; - }; + buildDTBs = kernelConf.DTB or false; in assert lib.versionOlder version "5.8" -> libelf != null; assert lib.versionAtLeast version "5.8" -> elfutils != null; -stdenv.mkDerivation ((drvAttrs config stdenv.hostPlatform.linux-kernel kernelPatches configfile) // { +stdenv.mkDerivation ({ pname = "linux"; - inherit version; - - enableParallelBuilding = true; + inherit version src; depsBuildBuild = [ buildPackages.stdenv.cc ]; nativeBuildInputs = [ perl bc nettools openssl rsync gmp libmpc mpfr zstd python3Minimal ] - ++ optional (stdenv.hostPlatform.linux-kernel.target == "uImage") buildPackages.ubootTools + ++ 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 $buildRoot + ''; + hardeningDisable = [ "bindnow" "format" "fortify" "stackprotector" "pic" "pie" ]; # Absolute paths for compilers avoid any PATH-clobbering issues. @@ -403,8 +217,198 @@ stdenv.mkDerivation ((drvAttrs config stdenv.hostPlatform.linux-kernel kernelPat "ARCH=${stdenv.hostPlatform.linuxArch}" ] ++ lib.optionals (stdenv.hostPlatform != stdenv.buildPlatform) [ "CROSS_COMPILE=${stdenv.cc.targetPrefix}" - ] ++ (stdenv.hostPlatform.linux-kernel.makeFlags or []) + ] ++ (kernelConf.makeFlags or []) ++ extraMakeFlags; karch = stdenv.hostPlatform.linuxArch; -} // (optionalAttrs (pos != null) { inherit pos; }))) + + buildFlags = [ + "DTC_FLAGS=-@" + "KBUILD_BUILD_VERSION=1-NixOS" + + # Set by default in the kernel since a73619a845d5, + # replicated here to apply to older versions. + # Makes __FILE__ relative to the build directory. + "KCPPFLAGS=-fmacro-prefix-map=$(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 /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" ]; +}))