initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP

gen_initramfs.sh has an internal dependency on KBUILD_BUILD_TIMESTAMP
for generating file mtimes that is not exposed to make, so changing
KBUILD_BUILD_TIMESTAMP will not trigger a rebuild of the archive.

Declare the mtime date as a new parameter to gen_initramfs.sh to encode
KBUILD_BUILD_TIMESTAMP in the shell command, thereby making make aware
of the dependency.

It will rebuild if KBUILD_BUILD_TIMESTAMP changes or is newly set/unset.
It will _not_ rebuild if KBUILD_BUILD_TIMESTAMP is unset before and
after. This should be fine for anyone who doesn't care about setting
specific build times in the first place.

Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Tested-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This commit is contained in:
Benjamin Gray 2023-06-06 16:17:41 +10:00 committed by Masahiro Yamada
parent feb843a469
commit 7f8256ae0e
2 changed files with 10 additions and 7 deletions

View file

@ -64,6 +64,7 @@ quiet_cmd_initfs = GEN $@
$(CONFIG_SHELL) $< -o $@ -l $(obj)/.initramfs_data.cpio.d \
$(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
$(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID)) \
$(if $(KBUILD_BUILD_TIMESTAMP), -d "$(KBUILD_BUILD_TIMESTAMP)") \
$(ramfs-input)
# We rebuild initramfs_data.cpio if:

View file

@ -23,6 +23,7 @@ $0 [-o <file>] [-l <dep_list>] [-u <uid>] [-g <gid>] {-d | <cpio_source>} ...
-g <gid> Group ID to map to group ID 0 (root).
<gid> is only meaningful if <cpio_source> is a
directory. "squash" forces all files to gid 0.
-d <date> Use date for all file mtime values
<cpio_source> File list or directory for cpio archive.
If <cpio_source> is a .cpio file it will be used
as direct input to initramfs.
@ -190,6 +191,7 @@ prog=$0
root_uid=0
root_gid=0
dep_list=
timestamp=
cpio_list=$(mktemp ${TMPDIR:-/tmp}/cpiolist.XXXXXX)
output="/dev/stdout"
@ -218,6 +220,13 @@ while [ $# -gt 0 ]; do
[ "$root_gid" = "-1" ] && root_gid=$(id -g || echo 0)
shift
;;
"-d") # date for file mtimes
timestamp="$(date -d"$1" +%s || :)"
if test -n "$timestamp"; then
timestamp="-t $timestamp"
fi
shift
;;
"-h")
usage
exit 0
@ -237,11 +246,4 @@ done
# If output_file is set we will generate cpio archive
# we are careful to delete tmp files
timestamp=
if test -n "$KBUILD_BUILD_TIMESTAMP"; then
timestamp="$(date -d"$KBUILD_BUILD_TIMESTAMP" +%s || :)"
if test -n "$timestamp"; then
timestamp="-t $timestamp"
fi
fi
usr/gen_init_cpio $timestamp $cpio_list > $output