linux-kernel-module-cheat/build

#!/usr/bin/env bash
set -eu
. common
arch=x86_64
rm -f br2_cli.gitignore
touch br2_cli.gitignore
configure=true
config_fragments='br2'
extra_make_args=''
gem5=false
j="$(($(nproc) - 2))"
linux_reconfigure=false
linux_kernel_custom_config_file=''
post_script_args=''
qemu_sdl='--enable-sdl --with-sdlabi=2.0'
v=0
while getopts 'a:B:b:CGgj:hIiK:klp:qSv' OPT; do
  case "$OPT" in
    a)
      arch="$OPTARG"
    ;;
    b)
      config_fragments="$config_fragments $OPTARG"
    ;;
    B)
      echo "$OPTARG" >> br2_cli.gitignore
    ;;
    C)
      configure=false
    ;;
    G)
      extra_make_args="$extra_make_args gem5-reconfigure"
      gem5=true
    ;;
    g)
      gem5=true
    ;;
    h)
      cat build-usage.adoc 1>&2
      exit
    ;;
    I)
      echo "
BR2_TARGET_ROOTFS_CPIO=n
BR2_TARGET_ROOTFS_EXT2=n
BR2_TARGET_ROOTFS_INITRAMFS=y
" >> br2_cli.gitignore
    ;;
    i)
      echo "
BR2_TARGET_ROOTFS_CPIO=y
BR2_TARGET_ROOTFS_EXT2=n
BR2_TARGET_ROOTFS_INITRAMFS=n
" >> br2_cli.gitignore
    ;;
    j)
      echo "$OPTARG" >> br2_cli.gitignore
    ;;
    K)
      linux_kernel_custom_config_file="$OPTARG"
    ;;
    k)
      extra_make_args="$extra_make_args kernel_module-reconfigure"
    ;;
    l)
      linux_reconfigure=true
      extra_make_args="$extra_make_args linux-reconfigure"
    ;;
    p)
      post_script_args="$OPTARG"
    ;;
    q)
      extra_make_args="$extra_make_args host-qemu-reconfigure"
    ;;
    S)
      qemu_sdl=''
    ;;
    v)
      v=1
    ;;
  esac
done
shift $(($OPTIND - 1))
extra_make_args="$extra_make_args $@"
set_common_vars "$arch" "$gem5"
config_file="${buildroot_out_dir}/.config"
case "$arch" in
  x86_64)
    defconfig=qemu_x86_64_defconfig
  ;;
  arm)
    defconfig=qemu_arm_versatile_defconfig
  ;;
  aarch64)
    defconfig=qemu_aarch64_virt_defconfig
  ;;
  mips64)
    defconfig=qemu_mips64r6_malta_defconfig
  ;;
esac
if ! "$gem5"; then
  config_fragments="$config_fragments br2_qemu"
fi
config_fragments="$config_fragments br2_cli.gitignore"

# Configure.
if "$configure"; then
  cd "${buildroot_dir}"
  for p in $(find "${root_dir}/buildroot_patches/" -maxdepth 1 -name '*.patch' -print); do
    patch -N -r - -p 1 <"$p" || :
  done
  make O="$buildroot_out_dir" BR2_EXTERNAL="../kernel_module:../gem5:../parsec-benchmark" "$defconfig"
  # TODO Can't get rid of these for now.
  # http://stackoverflow.com/questions/44078245/is-it-possible-to-use-config-fragments-with-buildroots-config
  for config_fragment in $config_fragments; do
    cat "../$config_fragment" >> "${config_file}"
  done
  printf "
BR2_JLEVEL=$j
BR2_DL_DIR=\"${common_dir}/dl\"
BR2_ROOTFS_POST_SCRIPT_ARGS=\"$post_script_args\"
" >> "${config_file}"
  if "$gem5"; then
    printf "BR2_PACKAGE_GEM5=y\n" >> "${config_file}"
    if [ -z "$linux_kernel_custom_config_file" ] && [ ! "$arch" = aarch64 ]; then
      f="../kernel_config_${arch_dir}"
      if [ -f "$f" ]; then
        printf "BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE=\"$f\"\n" >> "${config_file}"
      fi
    fi
  fi
  if [ -n "$linux_kernel_custom_config_file" ]; then
    f="../${linux_kernel_custom_config_file}"
    if [ -f "$f" ]; then
      printf "BR2_LINUX_KERNEL_CUSTOM_CONFIG_FILE=\"${f}\"\n" >> "${config_file}"
      if "${linux_reconfigure}"; then
        touch "$f"
      fi
    else
      echo "error: -K: file does not exist: ${linux_kernel_custom_config_file}" 1>&2
      exit 1
    fi
  else
    f=../kernel_config_fragment
    printf "BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES=\"${f}\"\n" >> "${config_file}"
    if "${linux_reconfigure}"; then
      # https://stackoverflow.com/questions/49260466/why-when-i-change-br2-linux-kernel-custom-config-file-and-run-make-linux-reconfi
      touch "$f"
    fi
  fi
  if [ "$arch" = 'mips64' ]; then
    # Workaround for:
    # http://lists.busybox.net/pipermail/buildroot/2017-August/201053.html
    sed -Ei 's/^BR2_PACKAGE_LINUX_TOOLS_GPIO/BR2_PACKAGE_LINUX_TOOLS_GPIO=n/' "${config_file}"
  fi
  make O="$buildroot_out_dir" olddefconfig
fi

# Build.
mkdir -p \
  "${gem5_out_dir}" \
  "${qemu_out_dir}" \
  "${root_dir}/9p" \
;
cd "${buildroot_dir}"
# HOST_QEMU_OPTS is a hack that happens to work because the QEMU package luckly uses += at all times.
# It shouldn't be necessary in the first place: https://bugs.busybox.net/show_bug.cgi?id=9936
#
# Even if were an autotools package, there is no general way currently to pass extra configs to it:
# https://stackoverflow.com/questions/44341188/how-to-pass-extra-custom-configure-autotools-options-to-a-buildroot-package/44341225#44341225
#
# BR2_ options may be given on the command line here, and they do have direct "define" effects.
# But this is generally bad, as it skips the Kconfig mechanism, e.g. it does not set defaults properly.
cmd="time \
  env \
  -u LD_LIBRARY_PATH \
  make \
  O='${buildroot_out_dir}' \
  HOST_QEMU_OPTS='--enable-debug --extra-cflags=-DDEBUG_PL061=1 --enable-trace-backends=simple ${qemu_sdl}' \
  V='$v' \
  ${extra_make_args} \
  all \
"
echo "$cmd" | tee "${root_dir}/build.log"
eval "$cmd"