build_image & make_bootable: allow additional kernel cmdline args

In order to more easily test kernel commandline tweaks, ensure that
--boot_args is propagated to all kernel cmdline sinks.

This is useful for changing default schedulers and any other kernel argument
tweaks we may want to quickly test out.

TEST=build and tested x86-generic
BUG=none

Change-Id: I5138755aa8c5e32e7f117f18291d2ae197e95bef

Review URL: http://codereview.chromium.org/3644004

bin/cros_make_image_bootable

@@ -68,6 +68,9 @@ DEFINE_string usb_disk "/dev/sdb3" \
 DEFINE_boolean cleanup_dirs ${FLAGS_TRUE} \
   "Whether the mount dirs should be removed on completion."
 
+DEFINE_string boot_args "noinitrd" \
+  "Additional boot arguments to pass to the commandline"
+
 DEFINE_integer rootfs_size 720 \
   "rootfs filesystem size in MBs."
 # ceil(0.1 * rootfs_size) is a good minimum.
@@ -157,6 +160,7 @@ make_image_bootable() {
     --hd_vblock="${FLAGS_output_dir}/vmlinuz_hd.vblock" \
     --vmlinuz="${FLAGS_rootfs_mountpoint}/boot/vmlinuz" \
     --working_dir="${FLAGS_output_dir}" \
+    --boot_args="${FLAGS_boot_args}" \
     --keep_work \
     --rootfs_image=${root_dev} \
     --rootfs_hash=${FLAGS_rootfs_hash} \

build_image

@@ -63,6 +63,8 @@ DEFINE_boolean preserve ${FLAGS_FALSE} \
 kernel/firmware not updated)"
 DEFINE_boolean fast ${DEFAULT_FAST} \
   "Call many emerges in parallel"
+DEFINE_string boot_args "noinitrd" \
+  "Additional boot arguments to pass to the commandline"
 
 DEFINE_string usb_disk /dev/sdb3 \
   "Path syslinux should use to do a usb boot. Default: /dev/sdb3"
@@ -346,6 +348,7 @@ create_boot_desc() {
   cat <<EOF > ${OUTPUT_DIR}/boot.desc
   --arch="${ARCH}"
   --output_dir="${OUTPUT_DIR}"
+  --boot_args="${FLAGS_boot_args}"
   --rootfs_size="${FLAGS_rootfs_size}"
   --rootfs_hash_pad="${FLAGS_rootfs_hash_pad}"
   --rootfs_hash="${ROOT_FS_HASH}"
@@ -615,6 +618,7 @@ create_base_image() {
   ${SCRIPTS_DIR}/create_legacy_bootloader_templates.sh \
     --arch=${ARCH} \
     --to="${ROOT_FS_DIR}"/boot \
+    --boot_args="${FLAGS_boot_args}" \
     --install \
     ${enable_rootfs_verification}
 

create_legacy_bootloader_templates.sh

@@ -37,7 +37,7 @@ set -e
 
 # Common kernel command-line args
 common_args="quiet console=tty2 init=/sbin/init boot=local rootwait ro noresume"
-common_args="${common_args} noswap loglevel=1"
+common_args="${common_args} noswap loglevel=1 ${FLAGS_boot_args}"
 
 # Common verified boot command-line args
 verity_common="dm_verity.error_behavior=${FLAGS_verity_error_behavior}"