update_kernel.sh

#!/bin/bash

# Copyright (c) 2009-2010 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

# Script to update the kernel on a live running ChromiumOS instance.

# Load common constants.  This should be the first executable line.
# The path to common.sh should be relative to your script's location.

. "$(dirname $0)/common.sh"
. "$(dirname $0)/remote_access.sh"

DEFINE_string board "" "Override board reported by target"
DEFINE_string partition "" "Override kernel partition reported by target"

function cleanup {
  cleanup_remote_access
  rm -rf "${TMP}"
}

# Ask the target what the kernel partition is
function learn_partition() {
  [ -n "${FLAGS_partition}" ] && return
  remote_sh cat /proc/cmdline
  if echo "${REMOTE_OUT}" | grep -q "/dev/sda3"; then
    FLAGS_partition="/dev/sda2"
  else
    FLAGS_partition="/dev/sda4"
  fi
  if [ -z "${FLAGS_partition}" ]; then
    error "Partition required"
    exit 1
  fi
  info "Target reports kernel partition is ${FLAGS_partition}"
}

function main() {
  assert_outside_chroot

  cd $(dirname "$0")

  FLAGS "$@" || exit 1
  eval set -- "${FLAGS_ARGV}"

  set -e

  trap cleanup EXIT

  TMP=$(mktemp -d /tmp/image_to_live.XXXX)

  remote_access_init

  learn_board

  remote_sh uname -r -v

  old_kernel="${REMOTE_OUT}"

  cmd="vbutil_kernel --pack new_kern.bin \
       --keyblock /usr/share/vboot/devkeys/kernel.keyblock \
       --signprivate /usr/share/vboot/devkeys/kernel_data_key.vbprivk \
       --version 1 \
       --config ../build/images/${FLAGS_board}/latest/config.txt \
       --bootloader /lib64/bootstub/bootstub.efi \
       --vmlinuz /build/${FLAGS_board}/boot/vmlinuz"

  ./enter_chroot.sh -- ${cmd}

  learn_partition

  remote_cp_to new_kern.bin /tmp

  remote_sh dd if=/tmp/new_kern.bin of="${FLAGS_partition}"

  remote_reboot

  remote_sh uname -r -v

  info "old kernel: ${old_kernel}"

  info "new kernel: ${REMOTE_OUT}"
}

main $@