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build.sh
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build.sh
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#!/bin/bash
# Copyright (C) 2019 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# Usage:
# build/build.sh <make options>*
# or:
# To define custom out and dist directories:
# OUT_DIR=<out dir> DIST_DIR=<dist dir> build/build.sh <make options>*
# To use a custom build config:
# BUILD_CONFIG=<path to the build.config> <make options>*
#
# Examples:
# To define custom out and dist directories:
# OUT_DIR=output DIST_DIR=dist build/build.sh -j24 V=1
# To use a custom build config:
# BUILD_CONFIG=common/build.config.gki.aarch64 build/build.sh -j24 V=1
#
# The following environment variables are considered during execution:
#
# BUILD_CONFIG
# Build config file to initialize the build environment from. The location
# is to be defined relative to the repo root directory.
# Defaults to 'build.config'.
#
# BUILD_CONFIG_FRAGMENTS
# A whitespace-separated list of additional build config fragments to be
# sourced after the main build config file. Typically used for sanitizers or
# other special builds.
#
# OUT_DIR
# Base output directory for the kernel build.
# Defaults to <REPO_ROOT>/out/<BRANCH>.
#
# DIST_DIR
# Base output directory for the kernel distribution.
# Defaults to <OUT_DIR>/dist
#
# MAKE_GOALS
# List of targets passed to Make when compiling the kernel.
# Typically: Image, modules, and a DTB (if applicable).
#
# EXT_MODULES
# Space separated list of external kernel modules to be build.
#
# EXT_MODULES_MAKEFILE
# Location of a makefile to build external modules. If set, it will get
# called with all the necessary parameters to build and install external
# modules. This allows for building them in parallel using makefile
# parallelization.
#
# UNSTRIPPED_MODULES
# Space separated list of modules to be copied to <DIST_DIR>/unstripped
# for debugging purposes.
#
# COMPRESS_UNSTRIPPED_MODULES
# If set to "1", then compress the unstripped modules into a tarball.
#
# CC
# Override compiler to be used. (e.g. CC=clang) Specifying CC=gcc
# effectively unsets CC to fall back to the default gcc detected by kbuild
# (including any target triplet). To use a custom 'gcc' from PATH, use an
# absolute path, e.g. CC=/usr/local/bin/gcc
#
# LD
# Override linker (flags) to be used.
#
# HERMETIC_TOOLCHAIN
# When set, the PATH during kernel build will be restricted to a set of
# known prebuilt directories and selected host tools that are usually not
# provided by prebuilt toolchains.
#
# ADDITIONAL_HOST_TOOLS
# A whitespace separated set of tools that will be allowed to be used from
# the host when running the build with HERMETIC_TOOLCHAIN=1.
#
# ABI_DEFINITION
# Location of the abi definition file relative to <REPO_ROOT>/KERNEL_DIR
# If defined (usually in build.config), also copy that abi definition to
# <OUT_DIR>/dist/abi.xml when creating the distribution.
#
# KMI_SYMBOL_LIST
# Location of the main KMI symbol list file relative to
# <REPO_ROOT>/KERNEL_DIR If defined (usually in build.config), also copy
# that symbol list definition to <OUT_DIR>/dist/abi_symbollist when
# creating the distribution.
#
# ADDITIONAL_KMI_SYMBOL_LISTS
# Location of secondary KMI symbol list files relative to
# <REPO_ROOT>/KERNEL_DIR. If defined, these additional symbol lists will be
# appended to the main one before proceeding to the distribution creation.
#
# KMI_ENFORCED
# This is an indicative option to signal that KMI is enforced in this build
# config. If set to "1", downstream KMI checking tools might respect it and
# react to it by failing if KMI differences are detected.
#
# GENERATE_VMLINUX_BTF
# If set to "1", generate a vmlinux.btf that is stripped off any debug
# symbols, but contains type and symbol information within a .BTF section.
# This is suitable for ABI analysis through BTF.
#
# Environment variables to influence the stages of the kernel build.
#
# SKIP_MRPROPER
# if set to "1", skip `make mrproper`
#
# SKIP_DEFCONFIG
# if set to "1", skip `make defconfig`
#
# SKIP_IF_VERSION_MATCHES
# if defined, skip compiling anything if the kernel version in vmlinux
# matches the expected kernel version. This is useful for mixed build, where
# GKI kernel does not change frequently and we can simply skip everything
# in build.sh. Note: if the expected version string contains "dirty", then
# this flag would have not cause build.sh to exit early.
#
# PRE_DEFCONFIG_CMDS
# Command evaluated before `make defconfig`
#
# POST_DEFCONFIG_CMDS
# Command evaluated after `make defconfig` and before `make`.
#
# POST_KERNEL_BUILD_CMDS
# Command evaluated after `make`.
#
# LTO=[full|thin|none]
# If set to "full", force any kernel with LTO_CLANG support to be built
# with full LTO, which is the most optimized method. This is the default,
# but can result in very slow build times, especially when building
# incrementally. (This mode does not require CFI to be disabled.)
# If set to "thin", force any kernel with LTO_CLANG support to be built
# with ThinLTO, which trades off some optimizations for incremental build
# speed. This is nearly always what you want for local development. (This
# mode does not require CFI to be disabled.)
# If set to "none", force any kernel with LTO_CLANG support to be built
# without any LTO (upstream default), which results in no optimizations
# and also disables LTO-dependent features like CFI. This mode is not
# recommended because CFI will not be able to catch bugs if it is
# disabled.
#
# TAGS_CONFIG
# if defined, calls ./scripts/tags.sh utility with TAGS_CONFIG as argument
# and exit once tags have been generated
#
# IN_KERNEL_MODULES
# if defined, install kernel modules
#
# SKIP_EXT_MODULES
# if defined, skip building and installing of external modules
#
# DO_NOT_STRIP_MODULES
# if set to "1", keep debug information for distributed modules.
# Note, modules will still be stripped when copied into the ramdisk.
#
# EXTRA_CMDS
# Command evaluated after building and installing kernel and modules.
#
# DIST_CMDS
# Command evaluated after copying files to DIST_DIR
#
# SKIP_CP_KERNEL_HDR
# if defined, skip installing kernel headers.
#
# BUILD_BOOT_IMG
# if defined, build a boot.img binary that can be flashed into the 'boot'
# partition of an Android device. The boot image contains a header as per the
# format defined by https://source.android.com/devices/bootloader/boot-image-header
# followed by several components like kernel, ramdisk, DTB etc. The ramdisk
# component comprises of a GKI ramdisk cpio archive concatenated with a
# vendor ramdisk cpio archive which is then gzipped. It is expected that
# all components are present in ${DIST_DIR}.
#
# When the BUILD_BOOT_IMG flag is defined, the following flags that point to the
# various components needed to build a boot.img also need to be defined.
# - MKBOOTIMG_PATH=<path to the mkbootimg.py script which builds boot.img>
# (defaults to tools/mkbootimg/mkbootimg.py)
# - GKI_RAMDISK_PREBUILT_BINARY=<Name of the GKI ramdisk prebuilt which includes
# the generic ramdisk components like init and the non-device-specific rc files>
# - VENDOR_RAMDISK_BINARY=<Space separated list of vendor ramdisk binaries
# which includes the device-specific components of ramdisk like the fstab
# file and the device-specific rc files. If specifying multiple vendor ramdisks
# and identical file paths exist in the ramdisks, the file from last ramdisk is used.>
# - KERNEL_BINARY=<name of kernel binary, eg. Image.lz4, Image.gz etc>
# - BOOT_IMAGE_HEADER_VERSION=<version of the boot image header>
# (defaults to 3)
# - KERNEL_CMDLINE=<string of kernel parameters for boot>
# - KERNEL_VENDOR_CMDLINE=<string of kernel parameters for vendor boot image,
# vendor_boot when BOOT_IMAGE_HEADER_VERSION >= 3; boot otherwise>
# - VENDOR_FSTAB=<Path to the vendor fstab to be included in the vendor
# ramdisk>
# - TAGS_OFFSET=<physical address for kernel tags>
# - RAMDISK_OFFSET=<ramdisk physical load address>
# If the BOOT_IMAGE_HEADER_VERSION is less than 3, two additional variables must
# be defined:
# - BASE_ADDRESS=<base address to load the kernel at>
# - PAGE_SIZE=<flash page size>
# If BOOT_IMAGE_HEADER_VERSION >= 3, a vendor_boot image will be built
# unless SKIP_VENDOR_BOOT is defined. A vendor_boot will also be generated if
# BUILD_VENDOR_BOOT_IMG is set.
#
# BUILD_VENDOR_BOOT_IMG is incompatible with SKIP_VENDOR_BOOT, and is effectively a
# nop if BUILD_BOOT_IMG is set.
# - MODULES_LIST=<file to list of modules> list of modules to use for
# vendor_boot.modules.load. If this property is not set, then the default
# modules.load is used.
# - TRIM_UNUSED_MODULES. If set, then modules not mentioned in
# modules.load are removed from initramfs. If MODULES_LIST is unset, then
# having this variable set effectively becomes a no-op.
# - MODULES_BLOCKLIST=<modules.blocklist file> A list of modules which are
# blocked from being loaded. This file is copied directly to staging directory,
# and should be in the format:
# blocklist module_name
# - MKBOOTIMG_EXTRA_ARGS=<space-delimited mkbootimg arguments>
# Refer to: ./mkbootimg.py --help
# If BOOT_IMAGE_HEADER_VERSION >= 4, the following variable can be defined:
# - VENDOR_BOOTCONFIG=<string of bootconfig parameters>
# - INITRAMFS_VENDOR_RAMDISK_FRAGMENT_NAME=<name of the ramdisk fragment>
# If BUILD_INITRAMFS is specified, then build the .ko and depmod files as
# a standalone vendor ramdisk fragment named as the given string.
# - INITRAMFS_VENDOR_RAMDISK_FRAGMENT_MKBOOTIMG_ARGS=<mkbootimg arguments>
# Refer to: https://source.android.com/devices/bootloader/partitions/vendor-boot-partitions#mkbootimg-arguments
#
# VENDOR_RAMDISK_CMDS
# When building vendor boot image, VENDOR_RAMDISK_CMDS enables the build
# config file to specify command(s) for further altering the prebuilt vendor
# ramdisk binary. For example, the build config file could add firmware files
# on the vendor ramdisk (lib/firmware) for testing purposes.
#
# AVB_SIGN_BOOT_IMG
# if defined, sign the boot image using the AVB_BOOT_KEY. Refer to
# https://android.googlesource.com/platform/external/avb/+/master/README.md
# for details on what Android Verified Boot is and how it works. The kernel
# prebuilt tool `avbtool` is used for signing.
#
# When AVB_SIGN_BOOT_IMG is defined, the following flags need to be
# defined:
# - AVB_BOOT_PARTITION_SIZE=<size of the boot partition in bytes>
# - AVB_BOOT_KEY=<absolute path to the key used for signing> The Android test
# key has been uploaded to the kernel/prebuilts/build-tools project here:
# https://android.googlesource.com/kernel/prebuilts/build-tools/+/refs/heads/master/linux-x86/share/avb
# - AVB_BOOT_ALGORITHM=<AVB_BOOT_KEY algorithm used> e.g. SHA256_RSA2048. For the
# full list of supported algorithms, refer to the enum AvbAlgorithmType in
# https://android.googlesource.com/platform/external/avb/+/refs/heads/master/libavb/avb_crypto.h
#
# BUILD_INITRAMFS
# if set to "1", build a ramdisk containing all .ko files and resulting
# depmod artifacts
#
# MODULES_OPTIONS
# A /lib/modules/modules.options file is created on the ramdisk containing
# the contents of this variable, lines should be of the form: options
# <modulename> <param1>=<val> <param2>=<val> ...
#
# MODULES_ORDER
# location of an optional file containing the list of modules that are
# expected to be built for the current configuration, in the modules.order
# format, relative to the kernel source tree.
#
# GKI_MODULES_LIST
# location of an optional file containing the list of GKI modules, relative
# to the kernel source tree. This should be set in downstream builds to
# ensure the ABI tooling correctly differentiates vendor/OEM modules and GKI
# modules. This should not be set in the upstream GKI build.config.
#
# VENDOR_DLKM_MODULES_LIST
# location (relative to the repo root directory) of an optional file
# containing the list of kernel modules which shall be copied into a
# vendor_dlkm partition image. Any modules passed into MODULES_LIST which
# become part of the vendor_boot.modules.load will be trimmed from the
# vendor_dlkm.modules.load.
#
# VENDOR_DLKM_MODULES_BLOCKLIST
# location (relative to the repo root directory) of an optional file
# containing a list of modules which are blocked from being loaded. This
# file is copied directly to the staging directory and should be in the
# format: blocklist module_name
#
# VENDOR_DLKM_PROPS
# location (relative to the repo root directory) of a text file containing
# the properties to be used for creation of a vendor_dlkm image
# (filesystem, partition size, etc). If this is not set (and
# VENDOR_DLKM_MODULES_LIST is), a default set of properties will be used
# which assumes an ext4 filesystem and a dynamic partition.
#
# LZ4_RAMDISK
# if set to "1", any ramdisks generated will be lz4 compressed instead of
# gzip compressed.
#
# TRIM_NONLISTED_KMI
# if set to "1", enable the CONFIG_UNUSED_KSYMS_WHITELIST kernel config
# option to un-export from the build any un-used and non-symbol-listed
# (as per KMI_SYMBOL_LIST) symbol.
#
# KMI_SYMBOL_LIST_STRICT_MODE
# if set to "1", add a build-time check between the KMI_SYMBOL_LIST and the
# KMI resulting from the build, to ensure they match 1-1.
#
# KMI_STRICT_MODE_OBJECTS
# optional list of objects to consider for the KMI_SYMBOL_LIST_STRICT_MODE
# check. Defaults to 'vmlinux'.
#
# GKI_DIST_DIR
# optional directory from which to copy GKI artifacts into DIST_DIR
#
# GKI_BUILD_CONFIG
# If set, builds a second set of kernel images using GKI_BUILD_CONFIG to
# perform a "mixed build." Mixed builds creates "GKI kernel" and "vendor
# modules" from two different trees. The GKI kernel tree can be the Android
# Common Kernel and the vendor modules tree can be a complete vendor kernel
# tree. GKI_DIST_DIR (above) is set and the GKI kernel's DIST output is
# copied to this DIST output. This allows a vendor tree kernel image to be
# effectively discarded and a GKI kernel Image used from an Android Common
# Kernel. Any variables prefixed with GKI_ are passed into into the GKI
# kernel's build.sh invocation.
#
# This is incompatible with GKI_PREBUILTS_DIR.
#
# GKI_PREBUILTS_DIR
# If set, copies an existing set of GKI kernel binaries to the DIST_DIR to
# perform a "mixed build," as with GKI_BUILD_CONFIG. This allows you to
# skip the additional compilation, if interested.
#
# This is incompatible with GKI_BUILD_CONFIG.
#
# The following must be present:
# vmlinux
# System.map
# vmlinux.symvers
# modules.builtin
# modules.builtin.modinfo
# Image.lz4
#
# DTS_EXT_DIR
# Set this variable to compile an out-of-tree device tree. The value of
# this variable is set to the kbuild variable "dtstree" which is used to
# compile the device tree. If this is set, then it's likely the dt-bindings
# are out-of-tree as well. So be sure to set DTC_INCLUDE in the
# BUILD_CONFIG file to the include path containing the dt-bindings.
#
# Note: For historic reasons, internally, OUT_DIR will be copied into
# COMMON_OUT_DIR, and OUT_DIR will be then set to
# ${COMMON_OUT_DIR}/${KERNEL_DIR}. This has been done to accommodate existing
# build.config files that expect ${OUT_DIR} to point to the output directory of
# the kernel build.
#
# The kernel is built in ${COMMON_OUT_DIR}/${KERNEL_DIR}.
# Out-of-tree modules are built in ${COMMON_OUT_DIR}/${EXT_MOD} where
# ${EXT_MOD} is the path to the module source code.
set -e
# Save environment for mixed build support.
OLD_ENVIRONMENT=$(mktemp)
export -p > ${OLD_ENVIRONMENT}
# rel_path <to> <from>
# Generate relative directory path to reach directory <to> from <from>
function rel_path() {
local to=$1
local from=$2
local path=
local stem=
local prevstem=
[ -n "$to" ] || return 1
[ -n "$from" ] || return 1
to=$(readlink -e "$to")
from=$(readlink -e "$from")
[ -n "$to" ] || return 1
[ -n "$from" ] || return 1
stem=${from}/
while [ "${to#$stem}" == "${to}" -a "${stem}" != "${prevstem}" ]; do
prevstem=$stem
stem=$(readlink -e "${stem}/..")
[ "${stem%/}" == "${stem}" ] && stem=${stem}/
path=${path}../
done
echo ${path}${to#$stem}
}
# $1 directory of kernel modules ($1/lib/modules/x.y)
# $2 flags to pass to depmod
# $3 kernel version
function run_depmod() {
(
local ramdisk_dir=$1
local DEPMOD_OUTPUT
cd ${ramdisk_dir}
if ! DEPMOD_OUTPUT="$(depmod $2 -F ${DIST_DIR}/System.map -b . $3 2>&1)"; then
echo "$DEPMOD_OUTPUT" >&2
exit 1
fi
echo "$DEPMOD_OUTPUT"
if { echo "$DEPMOD_OUTPUT" | grep -q "needs unknown symbol"; }; then
echo "ERROR: kernel module(s) need unknown symbol(s)" >&2
exit 1
fi
)
}
# $1 MODULES_LIST, <File contains the list of modules that should go in the ramdisk>
# $2 MODULES_STAGING_DIR <The directory to look for all the compiled modules>
# $3 IMAGE_STAGING_DIR <The destination directory in which MODULES_LIST is
# expected, and it's corresponding modules.* files>
# $4 MODULES_BLOCKLIST, <File contains the list of modules to prevent from loading>
# $5 flags to pass to depmod
function create_modules_staging() {
local modules_list_file=$1
local src_dir=$(echo $2/lib/modules/*)
local version=$(basename "${src_dir}")
local dest_dir=$3/lib/modules/${version}
local dest_stage=$3
local modules_blocklist_file=$4
local depmod_flags=$5
rm -rf ${dest_dir}
mkdir -p ${dest_dir}/kernel
find ${src_dir}/kernel/ -maxdepth 1 -mindepth 1 \
-exec cp -r {} ${dest_dir}/kernel/ \;
# The other modules.* files will be generated by depmod
cp ${src_dir}/modules.order ${dest_dir}/modules.order
cp ${src_dir}/modules.builtin ${dest_dir}/modules.builtin
if [[ -n "${EXT_MODULES}" ]] || [[ -n "${EXT_MODULES_MAKEFILE}" ]]; then
mkdir -p ${dest_dir}/extra/
cp -r ${src_dir}/extra/* ${dest_dir}/extra/
(cd ${dest_dir}/ && \
find extra -type f -name "*.ko" | sort >> modules.order)
fi
if [ "${DO_NOT_STRIP_MODULES}" = "1" ]; then
# strip debug symbols off initramfs modules
find ${dest_dir} -type f -name "*.ko" \
-exec ${OBJCOPY:-${CROSS_COMPILE}objcopy} --strip-debug {} \;
fi
if [ -n "${modules_list_file}" ]; then
echo "========================================================"
echo " Reducing modules.order to:"
# Need to make sure we can find modules_list_file from the staging dir
if [[ -f "${ROOT_DIR}/${modules_list_file}" ]]; then
modules_list_file="${ROOT_DIR}/${modules_list_file}"
elif [[ "${modules_list_file}" != /* ]]; then
echo "modules list must be an absolute path or relative to ${ROOT_DIR}: ${modules_list_file}"
exit 1
elif [[ ! -f "${modules_list_file}" ]]; then
echo "Failed to find modules list: ${modules_list_file}"
exit 1
fi
local modules_list_filter=$(mktemp)
local old_modules_list=$(mktemp)
# Remove all lines starting with "#" (comments)
# Exclamation point makes interpreter ignore the exit code under set -e
! grep -v "^\#" ${modules_list_file} > ${modules_list_filter}
# grep the modules.order for any KOs in the modules list
cp ${dest_dir}/modules.order ${old_modules_list}
! grep -w -f ${modules_list_filter} ${old_modules_list} > ${dest_dir}/modules.order
rm -f ${modules_list_filter} ${old_modules_list}
cat ${dest_dir}/modules.order | sed -e "s/^/ /"
fi
if [ -n "${modules_blocklist_file}" ]; then
# Need to make sure we can find modules_blocklist_file from the staging dir
if [[ -f "${ROOT_DIR}/${modules_blocklist_file}" ]]; then
modules_blocklist_file="${ROOT_DIR}/${modules_blocklist_file}"
elif [[ "${modules_blocklist_file}" != /* ]]; then
echo "modules blocklist must be an absolute path or relative to ${ROOT_DIR}: ${modules_blocklist_file}"
exit 1
elif [[ ! -f "${modules_blocklist_file}" ]]; then
echo "Failed to find modules blocklist: ${modules_blocklist_file}"
exit 1
fi
cp ${modules_blocklist_file} ${dest_dir}/modules.blocklist
fi
if [ -n "${TRIM_UNUSED_MODULES}" ]; then
echo "========================================================"
echo " Trimming unused modules"
local used_blocklist_modules=$(mktemp)
if [ -f ${dest_dir}/modules.blocklist ]; then
# TODO: the modules blocklist could contain module aliases instead of the filename
sed -n -E -e 's/blocklist (.+)/\1/p' ${dest_dir}/modules.blocklist > $used_blocklist_modules
fi
# Trim modules from tree that aren't mentioned in modules.order
(
cd ${dest_dir}
find * -type f -name "*.ko" | grep -v -w -f modules.order -f $used_blocklist_modules - | xargs -r rm
)
rm $used_blocklist_modules
fi
# Re-run depmod to detect any dependencies between in-kernel and external
# modules. Then, create modules.order based on all the modules compiled.
run_depmod ${dest_stage} "${depmod_flags}" "${version}"
cp ${dest_dir}/modules.order ${dest_dir}/modules.load
}
function build_vendor_dlkm() {
echo "========================================================"
echo " Creating vendor_dlkm image"
create_modules_staging "${VENDOR_DLKM_MODULES_LIST}" "${MODULES_STAGING_DIR}" \
"${VENDOR_DLKM_STAGING_DIR}" "${VENDOR_DLKM_MODULES_BLOCKLIST}"
local vendor_dlkm_modules_root_dir=$(echo ${VENDOR_DLKM_STAGING_DIR}/lib/modules/*)
local vendor_dlkm_modules_load=${vendor_dlkm_modules_root_dir}/modules.load
if [ -f ${vendor_dlkm_modules_root_dir}/modules.blocklist ]; then
cp ${vendor_dlkm_modules_root_dir}/modules.blocklist ${DIST_DIR}/vendor_dlkm.modules.blocklist
fi
# Modules loaded in vendor_boot should not be loaded in vendor_dlkm.
if [ -f ${DIST_DIR}/vendor_boot.modules.load ]; then
local stripped_modules_load="$(mktemp)"
! grep -x -v -F -f ${DIST_DIR}/vendor_boot.modules.load \
${vendor_dlkm_modules_load} > ${stripped_modules_load}
mv -f ${stripped_modules_load} ${vendor_dlkm_modules_load}
fi
cp ${vendor_dlkm_modules_load} ${DIST_DIR}/vendor_dlkm.modules.load
local vendor_dlkm_props_file
if [ -z "${VENDOR_DLKM_PROPS}" ]; then
vendor_dlkm_props_file="$(mktemp)"
echo -e "vendor_dlkm_fs_type=ext4\n" >> ${vendor_dlkm_props_file}
echo -e "use_dynamic_partition_size=true\n" >> ${vendor_dlkm_props_file}
echo -e "ext_mkuserimg=mkuserimg_mke2fs\n" >> ${vendor_dlkm_props_file}
echo -e "ext4_share_dup_blocks=true\n" >> ${vendor_dlkm_props_file}
else
vendor_dlkm_props_file="${VENDOR_DLKM_PROPS}"
if [[ -f "${ROOT_DIR}/${vendor_dlkm_props_file}" ]]; then
vendor_dlkm_props_file="${ROOT_DIR}/${vendor_dlkm_props_file}"
elif [[ "${vendor_dlkm_props_file}" != /* ]]; then
echo "VENDOR_DLKM_PROPS must be an absolute path or relative to ${ROOT_DIR}: ${vendor_dlkm_props_file}"
exit 1
elif [[ ! -f "${vendor_dlkm_props_file}" ]]; then
echo "Failed to find VENDOR_DLKM_PROPS: ${vendor_dlkm_props_file}"
exit 1
fi
fi
build_image "${VENDOR_DLKM_STAGING_DIR}" "${vendor_dlkm_props_file}" \
"${DIST_DIR}/vendor_dlkm.img" /dev/null
}
export ROOT_DIR=$(readlink -f $(dirname $0)/..)
# For module file Signing with the kernel (if needed)
FILE_SIGN_BIN=scripts/sign-file
SIGN_SEC=certs/signing_key.pem
SIGN_CERT=certs/signing_key.x509
SIGN_ALGO=sha512
# Save environment parameters before being overwritten by sourcing
# BUILD_CONFIG.
CC_ARG="${CC}"
source "${ROOT_DIR}/build/_setup_env.sh"
MAKE_ARGS=( "$@" )
export MAKEFLAGS="-j$(nproc) ${MAKEFLAGS}"
export MODULES_STAGING_DIR=$(readlink -m ${COMMON_OUT_DIR}/staging)
export MODULES_PRIVATE_DIR=$(readlink -m ${COMMON_OUT_DIR}/private)
export KERNEL_UAPI_HEADERS_DIR=$(readlink -m ${COMMON_OUT_DIR}/kernel_uapi_headers)
export INITRAMFS_STAGING_DIR=${MODULES_STAGING_DIR}/initramfs_staging
export VENDOR_DLKM_STAGING_DIR=${MODULES_STAGING_DIR}/vendor_dlkm_staging
export MKBOOTIMG_STAGING_DIR="${MODULES_STAGING_DIR}/mkbootimg_staging"
if [ -n "${SKIP_VENDOR_BOOT}" -a -n "${BUILD_VENDOR_BOOT_IMG}" ]; then
echo "ERROR: SKIP_VENDOR_BOOT is incompatible with BUILD_VENDOR_BOOT_IMG." >&2
exit 1
fi
if [ -n "${GKI_BUILD_CONFIG}" ]; then
if [ -n "${GKI_PREBUILTS_DIR}" ]; then
echo "ERROR: GKI_BUILD_CONFIG is incompatible with GKI_PREBUILTS_DIR." >&2
exit 1
fi
GKI_OUT_DIR=${GKI_OUT_DIR:-${COMMON_OUT_DIR}/gki_kernel}
GKI_DIST_DIR=${GKI_DIST_DIR:-${GKI_OUT_DIR}/dist}
if [[ "${MAKE_GOALS}" =~ image|Image|vmlinux ]]; then
echo " Compiling Image and vmlinux in device kernel is not supported in mixed build mode"
exit 1
fi
# Inherit SKIP_MRPROPER, LTO, SKIP_DEFCONFIG unless overridden by corresponding GKI_* variables
GKI_ENVIRON=("SKIP_MRPROPER=${SKIP_MRPROPER}" "LTO=${LTO}" "SKIP_DEFCONFIG=${SKIP_DEFCONFIG}" "SKIP_IF_VERSION_MATCHES=${SKIP_IF_VERSION_MATCHES}")
# Explicitly unset EXT_MODULES since they should be compiled against the device kernel
GKI_ENVIRON+=("EXT_MODULES=")
# Explicitly unset GKI_BUILD_CONFIG in case it was set by in the old environment
# e.g. GKI_BUILD_CONFIG=common/build.config.gki.x86 ./build/build.sh would cause
# gki build recursively
GKI_ENVIRON+=("GKI_BUILD_CONFIG=")
# Any variables prefixed with GKI_ get set without that prefix in the GKI build environment
# e.g. GKI_BUILD_CONFIG=common/build.config.gki.aarch64 -> BUILD_CONFIG=common/build.config.gki.aarch64
GKI_ENVIRON+=($(export -p | sed -n -E -e 's/.* GKI_([^=]+=.*)$/\1/p' | tr '\n' ' '))
GKI_ENVIRON+=("OUT_DIR=${GKI_OUT_DIR}")
GKI_ENVIRON+=("DIST_DIR=${GKI_DIST_DIR}")
( env -i bash -c "source ${OLD_ENVIRONMENT}; rm -f ${OLD_ENVIRONMENT}; export ${GKI_ENVIRON[*]} ; ./build/build.sh" ) || exit 1
# Dist dir must have vmlinux.symvers, modules.builtin.modinfo, modules.builtin
MAKE_ARGS+=("KBUILD_MIXED_TREE=$(readlink -m ${GKI_DIST_DIR})")
else
rm -f ${OLD_ENVIRONMENT}
fi
BOOT_IMAGE_HEADER_VERSION=${BOOT_IMAGE_HEADER_VERSION:-3}
if [ -n "${DTS_EXT_DIR}" ]; then
if [[ "${MAKE_GOALS}" =~ dtbs|\.dtb|\.dtbo ]]; then
# DTS_EXT_DIR needs to be relative to KERNEL_DIR but we allow one to set
# it relative to ROOT_DIR for ease of use. So figure out what was used.
if [ -d "${ROOT_DIR}/${DTS_EXT_DIR}" ]; then
# DTS_EXT_DIR is currently relative to ROOT_DIR. So recalcuate it to be
# relative to KERNEL_DIR
DTS_EXT_DIR=$(rel_path ${ROOT_DIR}/${DTS_EXT_DIR} ${KERNEL_DIR})
elif [ ! -d "${KERNEL_DIR}/${DTS_EXT_DIR}" ]; then
echo "Couldn't find the dtstree -- ${DTS_EXT_DIR}" >&2
exit 1
fi
MAKE_ARGS+=("dtstree=${DTS_EXT_DIR}")
fi
fi
cd ${ROOT_DIR}
export CLANG_TRIPLE CROSS_COMPILE CROSS_COMPILE_COMPAT CROSS_COMPILE_ARM32 ARCH SUBARCH MAKE_GOALS
# Restore the previously saved CC argument that might have been overridden by
# the BUILD_CONFIG.
[ -n "${CC_ARG}" ] && CC="${CC_ARG}"
# CC=gcc is effectively a fallback to the default gcc including any target
# triplets. An absolute path (e.g., CC=/usr/bin/gcc) must be specified to use a
# custom compiler.
[ "${CC}" == "gcc" ] && unset CC && unset CC_ARG
TOOL_ARGS=()
# LLVM=1 implies what is otherwise set below; it is a more concise way of
# specifying CC=clang LD=ld.lld NM=llvm-nm OBJCOPY=llvm-objcopy <etc>, for
# newer kernel versions.
if [[ -n "${LLVM}" ]]; then
TOOL_ARGS+=("LLVM=1")
# Reset a bunch of variables that the kernel's top level Makefile does, just
# in case someone tries to use these binaries in this script such as in
# initramfs generation below.
HOSTCC=clang
HOSTCXX=clang++
CC=clang
LD=ld.lld
AR=llvm-ar
NM=llvm-nm
OBJCOPY=llvm-objcopy
OBJDUMP=llvm-objdump
READELF=llvm-readelf
OBJSIZE=llvm-size
STRIP=llvm-strip
else
if [ -n "${HOSTCC}" ]; then
TOOL_ARGS+=("HOSTCC=${HOSTCC}")
fi
if [ -n "${CC}" ]; then
TOOL_ARGS+=("CC=${CC}")
if [ -z "${HOSTCC}" ]; then
TOOL_ARGS+=("HOSTCC=${CC}")
fi
fi
if [ -n "${LD}" ]; then
TOOL_ARGS+=("LD=${LD}" "HOSTLD=${LD}")
fi
if [ -n "${NM}" ]; then
TOOL_ARGS+=("NM=${NM}")
fi
if [ -n "${OBJCOPY}" ]; then
TOOL_ARGS+=("OBJCOPY=${OBJCOPY}")
fi
fi
if [ -n "${LLVM_IAS}" ]; then
TOOL_ARGS+=("LLVM_IAS=${LLVM_IAS}")
# Reset $AS for the same reason that we reset $CC etc above.
AS=clang
fi
if [ -n "${DEPMOD}" ]; then
TOOL_ARGS+=("DEPMOD=${DEPMOD}")
fi
if [ -n "${DTC}" ]; then
TOOL_ARGS+=("DTC=${DTC}")
fi
# Allow hooks that refer to $CC_LD_ARG to keep working until they can be
# updated.
CC_LD_ARG="${TOOL_ARGS[@]}"
DECOMPRESS_GZIP="gzip -c -d"
DECOMPRESS_LZ4="lz4 -c -d -l"
if [ -z "${LZ4_RAMDISK}" ] ; then
RAMDISK_COMPRESS="gzip -c -f"
RAMDISK_DECOMPRESS="${DECOMPRESS_GZIP}"
RAMDISK_EXT="gz"
else
RAMDISK_COMPRESS="lz4 -c -l -12 --favor-decSpeed"
RAMDISK_DECOMPRESS="${DECOMPRESS_LZ4}"
RAMDISK_EXT="lz4"
fi
if [ -n "${SKIP_IF_VERSION_MATCHES}" ]; then
if [ -f "${DIST_DIR}/vmlinux" ]; then
kernelversion="$(cd ${KERNEL_DIR} && make -s "${TOOL_ARGS[@]}" O=${OUT_DIR} kernelrelease)"
# Split grep into 2 steps. "Linux version" will always be towards top and fast to find. Don't
# need to search the entire vmlinux for it
if [[ ! "$kernelversion" =~ .*dirty.* ]] && \
grep -o -a -m1 "Linux version [^ ]* " ${DIST_DIR}/vmlinux | grep -q " ${kernelversion} " ; then
echo "========================================================"
echo " Skipping build because kernel version matches ${kernelversion}"
exit 0
fi
fi
fi
mkdir -p ${OUT_DIR} ${DIST_DIR}
if [ -n "${GKI_PREBUILTS_DIR}" ]; then
echo "========================================================"
echo " Copying GKI prebuilts"
GKI_PREBUILTS_DIR=$(readlink -m ${GKI_PREBUILTS_DIR})
if [ ! -d "${GKI_PREBUILTS_DIR}" ]; then
echo "ERROR: ${GKI_PREBULTS_DIR} does not exist." >&2
exit 1
fi
for file in ${GKI_PREBUILTS_DIR}/*; do
filename=$(basename ${file})
if ! $(cmp -s ${file} ${DIST_DIR}/${filename}); then
cp -v ${file} ${DIST_DIR}/${filename}
fi
done
MAKE_ARGS+=("KBUILD_MIXED_TREE=${GKI_PREBUILTS_DIR}")
fi
echo "========================================================"
echo " Setting up for build"
if [ "${SKIP_MRPROPER}" != "1" ] ; then
set -x
(cd ${KERNEL_DIR} && make "${TOOL_ARGS[@]}" O=${OUT_DIR} "${MAKE_ARGS[@]}" mrproper)
set +x
fi
if [ -n "${PRE_DEFCONFIG_CMDS}" ]; then
echo "========================================================"
echo " Running pre-defconfig command(s):"
set -x
eval ${PRE_DEFCONFIG_CMDS}
set +x
fi
if [ "${SKIP_DEFCONFIG}" != "1" ] ; then
set -x
(cd ${KERNEL_DIR} && make "${TOOL_ARGS[@]}" O=${OUT_DIR} "${MAKE_ARGS[@]}" ${DEFCONFIG})
set +x
if [ -n "${POST_DEFCONFIG_CMDS}" ]; then
echo "========================================================"
echo " Running pre-make command(s):"
set -x
eval ${POST_DEFCONFIG_CMDS}
set +x
fi
fi
if [ "${LTO}" = "none" -o "${LTO}" = "thin" -o "${LTO}" = "full" ]; then
echo "========================================================"
echo " Modifying LTO mode to '${LTO}'"
set -x
if [ "${LTO}" = "none" ]; then
${KERNEL_DIR}/scripts/config --file ${OUT_DIR}/.config \
-d LTO_CLANG \
-e LTO_NONE \
-d LTO_CLANG_THIN \
-d LTO_CLANG_FULL \
-d THINLTO
elif [ "${LTO}" = "thin" ]; then
# This is best-effort; some kernels don't support LTO_THIN mode
# THINLTO was the old name for LTO_THIN, and it was 'default y'
${KERNEL_DIR}/scripts/config --file ${OUT_DIR}/.config \
-e LTO_CLANG \
-d LTO_NONE \
-e LTO_CLANG_THIN \
-d LTO_CLANG_FULL \
-e THINLTO
elif [ "${LTO}" = "full" ]; then
# THINLTO was the old name for LTO_THIN, and it was 'default y'
${KERNEL_DIR}/scripts/config --file ${OUT_DIR}/.config \
-e LTO_CLANG \
-d LTO_NONE \
-d LTO_CLANG_THIN \
-e LTO_CLANG_FULL \
-d THINLTO
fi
(cd ${OUT_DIR} && make "${TOOL_ARGS[@]}" O=${OUT_DIR} "${MAKE_ARGS[@]}" olddefconfig)
set +x
elif [ -n "${LTO}" ]; then
echo "LTO= must be one of 'none', 'thin' or 'full'."
exit 1
fi
if [ -n "${TAGS_CONFIG}" ]; then
echo "========================================================"
echo " Running tags command:"
set -x
(cd ${KERNEL_DIR} && SRCARCH=${ARCH} ./scripts/tags.sh ${TAGS_CONFIG})
set +x
exit 0
fi
# Truncate abi.prop file
ABI_PROP=${DIST_DIR}/abi.prop
: > ${ABI_PROP}
if [ -n "${ABI_DEFINITION}" ]; then
ABI_XML=${DIST_DIR}/abi.xml
echo "KMI_DEFINITION=abi.xml" >> ${ABI_PROP}
echo "KMI_MONITORED=1" >> ${ABI_PROP}
if [ "${KMI_ENFORCED}" = "1" ]; then
echo "KMI_ENFORCED=1" >> ${ABI_PROP}
fi
fi
if [ -n "${KMI_SYMBOL_LIST}" ]; then
ABI_SL=${DIST_DIR}/abi_symbollist
echo "KMI_SYMBOL_LIST=abi_symbollist" >> ${ABI_PROP}
fi
# define the kernel binary and modules archive in the $ABI_PROP
echo "KERNEL_BINARY=vmlinux" >> ${ABI_PROP}
if [ "${COMPRESS_UNSTRIPPED_MODULES}" = "1" ]; then
echo "MODULES_ARCHIVE=${UNSTRIPPED_MODULES_ARCHIVE}" >> ${ABI_PROP}
fi
# Copy the abi_${arch}.xml file from the sources into the dist dir
if [ -n "${ABI_DEFINITION}" ]; then
echo "========================================================"
echo " Copying abi definition to ${ABI_XML}"
pushd $ROOT_DIR/$KERNEL_DIR
cp "${ABI_DEFINITION}" ${ABI_XML}
popd
fi
# Copy the abi symbol list file from the sources into the dist dir
if [ -n "${KMI_SYMBOL_LIST}" ]; then
${ROOT_DIR}/build/copy_symbols.sh "$ABI_SL" "$ROOT_DIR/$KERNEL_DIR" \
"${KMI_SYMBOL_LIST}" ${ADDITIONAL_KMI_SYMBOL_LISTS}
pushd $ROOT_DIR/$KERNEL_DIR
if [ "${TRIM_NONLISTED_KMI}" = "1" ]; then
# Create the raw symbol list
cat ${ABI_SL} | \
${ROOT_DIR}/build/abi/flatten_symbol_list > \
${OUT_DIR}/abi_symbollist.raw
# Update the kernel configuration
./scripts/config --file ${OUT_DIR}/.config \
-d UNUSED_SYMBOLS -e TRIM_UNUSED_KSYMS \
--set-str UNUSED_KSYMS_WHITELIST ${OUT_DIR}/abi_symbollist.raw
(cd ${OUT_DIR} && \
make O=${OUT_DIR} "${TOOL_ARGS[@]}" "${MAKE_ARGS[@]}" olddefconfig)
# Make sure the config is applied
grep CONFIG_UNUSED_KSYMS_WHITELIST ${OUT_DIR}/.config > /dev/null || {
echo "ERROR: Failed to apply TRIM_NONLISTED_KMI kernel configuration" >&2
echo "Does your kernel support CONFIG_UNUSED_KSYMS_WHITELIST?" >&2
exit 1
}
elif [ "${KMI_SYMBOL_LIST_STRICT_MODE}" = "1" ]; then
echo "ERROR: KMI_SYMBOL_LIST_STRICT_MODE requires TRIM_NONLISTED_KMI=1" >&2
exit 1
fi
popd # $ROOT_DIR/$KERNEL_DIR
elif [ "${TRIM_NONLISTED_KMI}" = "1" ]; then
echo "ERROR: TRIM_NONLISTED_KMI requires a KMI_SYMBOL_LIST" >&2
exit 1
elif [ "${KMI_SYMBOL_LIST_STRICT_MODE}" = "1" ]; then
echo "ERROR: KMI_SYMBOL_LIST_STRICT_MODE requires a KMI_SYMBOL_LIST" >&2
exit 1
fi
echo "========================================================"
echo " Building kernel"
set -x
(cd ${OUT_DIR} && make O=${OUT_DIR} "${TOOL_ARGS[@]}" "${MAKE_ARGS[@]}" ${MAKE_GOALS})
set +x
if [ -n "${POST_KERNEL_BUILD_CMDS}" ]; then
echo "========================================================"
echo " Running post-kernel-build command(s):"
set -x
eval ${POST_KERNEL_BUILD_CMDS}
set +x
fi
if [ -n "${MODULES_ORDER}" ]; then
echo "========================================================"
echo " Checking the list of modules:"
if ! diff -u "${KERNEL_DIR}/${MODULES_ORDER}" "${OUT_DIR}/modules.order"; then
echo "ERROR: modules list out of date" >&2
echo "Update it with:" >&2
echo "cp ${OUT_DIR}/modules.order ${KERNEL_DIR}/${MODULES_ORDER}" >&2
exit 1
fi
fi
if [ "${KMI_SYMBOL_LIST_STRICT_MODE}" = "1" ]; then
echo "========================================================"
echo " Comparing the KMI and the symbol lists:"
set -x
${ROOT_DIR}/build/abi/compare_to_symbol_list "${OUT_DIR}/Module.symvers" \
"${OUT_DIR}/abi_symbollist.raw"
set +x
fi
rm -rf ${MODULES_STAGING_DIR}
mkdir -p ${MODULES_STAGING_DIR}
if [ "${DO_NOT_STRIP_MODULES}" != "1" ]; then
MODULE_STRIP_FLAG="INSTALL_MOD_STRIP=1"
fi
if [ "${BUILD_INITRAMFS}" = "1" -o -n "${IN_KERNEL_MODULES}" ]; then
echo "========================================================"
echo " Installing kernel modules into staging directory"
(cd ${OUT_DIR} && \
make O=${OUT_DIR} "${TOOL_ARGS[@]}" ${MODULE_STRIP_FLAG} \
INSTALL_MOD_PATH=${MODULES_STAGING_DIR} "${MAKE_ARGS[@]}" modules_install)
fi
if [[ -z "${SKIP_EXT_MODULES}" ]] && [[ -n "${EXT_MODULES_MAKEFILE}" ]]; then
echo "========================================================"
echo " Building and installing external modules using ${EXT_MODULES_MAKEFILE}"
make -f "${EXT_MODULES_MAKEFILE}" KERNEL_SRC=${ROOT_DIR}/${KERNEL_DIR} \
O=${OUT_DIR} ${TOOL_ARGS} ${MODULE_STRIP_FLAG} \
INSTALL_HDR_PATH="${KERNEL_UAPI_HEADERS_DIR}/usr" \
INSTALL_MOD_PATH=${MODULES_STAGING_DIR} "${MAKE_ARGS[@]}"
fi
if [[ -z "${SKIP_EXT_MODULES}" ]] && [[ -n "${EXT_MODULES}" ]]; then
echo "========================================================"
echo " Building external modules and installing them into staging directory"
for EXT_MOD in ${EXT_MODULES}; do
# The path that we pass in via the variable M needs to be a relative path
# relative to the kernel source directory. The source files will then be
# looked for in ${KERNEL_DIR}/${EXT_MOD_REL} and the object files (i.e. .o
# and .ko) files will be stored in ${OUT_DIR}/${EXT_MOD_REL}. If we
# instead set M to an absolute path, then object (i.e. .o and .ko) files
# are stored in the module source directory which is not what we want.
EXT_MOD_REL=$(rel_path ${ROOT_DIR}/${EXT_MOD} ${KERNEL_DIR})
# The output directory must exist before we invoke make. Otherwise, the
# build system behaves horribly wrong.
mkdir -p ${OUT_DIR}/${EXT_MOD_REL}
set -x
make -C ${EXT_MOD} M=${EXT_MOD_REL} KERNEL_SRC=${ROOT_DIR}/${KERNEL_DIR} \
O=${OUT_DIR} "${TOOL_ARGS[@]}" "${MAKE_ARGS[@]}"
make -C ${EXT_MOD} M=${EXT_MOD_REL} KERNEL_SRC=${ROOT_DIR}/${KERNEL_DIR} \
O=${OUT_DIR} "${TOOL_ARGS[@]}" ${MODULE_STRIP_FLAG} \
INSTALL_MOD_PATH=${MODULES_STAGING_DIR} \
INSTALL_HDR_PATH="${KERNEL_UAPI_HEADERS_DIR}/usr" \
"${MAKE_ARGS[@]}" modules_install
set +x
done