mirror of
https://git.yoctoproject.org/poky
synced 2026-05-08 17:19:20 +00:00
Juro Bystricky
55e9485735
Several tweaks to improve reproducibility: 1. If BUILD_REPRODUCIBLE_BINARIES == 1, set KBUILD_BUILD_TIMESTAMP to a reproducible value. This is either a non-zero SOURCE_DATE_EPOCH, or the value obtained from top entry of GIT repo, or (if there is no GIT repo) fallback to REPRODUCIBLE_TIMESTAMP_ROOTFS as the last resort. Also export KCONFIG_NOTIMESTAMP=1. 2. When compressing vmlinux.gz, use gzip "-n" option 3. Kernel and kernel modules contain hard coded paths referencing the host build system. This is usually because the source code contains __FILE__ at some place. This prevents binary reproducibility. However, some compilers allow remapping of the __FILE__ value. If we detect the compiler is capable of doing this, we replace the source path $(S) part of __FILE__ by a string "/kernel-source". For example: /data/master/build/tmp/work-shared/qemux86/kernel-source/drivers/media/v4l2-core/videobuf2-core.c will be replaced by a reproducible value: /kernel-source/drivers/media/v4l2-core/videobuf2-core.c. (From OE-Core rev: 012a70da7ae0617740cd0cf807d01c3cd912c823) Signed-off-by: Juro Bystricky <juro.bystricky@intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Poky
====
Poky is an integration of various components to form a complete prepackaged
build system and development environment. It features support for building
customised embedded device style images. There are reference demo images
featuring a X11/Matchbox/GTK themed UI called Sato. The system supports
cross-architecture application development using QEMU emulation and a
standalone toolchain and SDK with IDE integration.
Additional information on the specifics of hardware that Poky supports
is available in README.hardware. Further hardware support can easily be added
in the form of layers which extend the systems capabilities in a modular way.
As an integration layer Poky consists of several upstream projects such as
BitBake, OpenEmbedded-Core, Yocto documentation and various sources of information
e.g. for the hardware support. Poky is in turn a component of the Yocto Project.
The Yocto Project has extensive documentation about the system including a
reference manual which can be found at:
http://yoctoproject.org/documentation
OpenEmbedded-Core is a layer containing the core metadata for current versions
of OpenEmbedded. It is distro-less (can build a functional image with
DISTRO = "nodistro") and contains only emulated machine support.
For information about OpenEmbedded, see the OpenEmbedded website:
http://www.openembedded.org/
Where to Send Patches
=====================
As Poky is an integration repository (built using a tool called combo-layer),
patches against the various components should be sent to their respective
upstreams:
bitbake:
Git repository: http://git.openembedded.org/bitbake/
Mailing list: bitbake-devel@lists.openembedded.org
documentation:
Git repository: http://git.yoctoproject.org/cgit/cgit.cgi/yocto-docs/
Mailing list: yocto@yoctoproject.org
meta-poky, meta-yocto-bsp:
Git repository: http://git.yoctoproject.org/cgit/cgit.cgi/meta-yocto(-bsp)
Mailing list: poky@yoctoproject.org
Everything else should be sent to the OpenEmbedded Core mailing list. If in
doubt, check the oe-core git repository for the content you intend to modify.
Before sending, be sure the patches apply cleanly to the current oe-core git
repository.
Git repository: http://git.openembedded.org/openembedded-core/
Mailing list: openembedded-core@lists.openembedded.org
Note: The scripts directory should be treated with extra care as it is a mix of
oe-core and poky-specific files.