c3b3d7c14f
The cached revisions which are used to decide if a repository doesn't need to be updated are misleading when used in conjunction with mirror tarballs and can cause partial fetches to happen, resulting in unpack errors as repositories were not fetched. A concrete example: edk2-firmware in meta-arm is at version 202102 (ef91b0). This is built on the autobuilder so the source mirror contains the repository as a mirror tarball. If I build edk2-firmware 202102 the gitsm fetcher will initially download the top-level repository and then iterate into the submodules to also fetch those repositories, including cmocka from cryptomilk.org. edk2-firmware will then unpack and build successfully. I then update edk2-firmware to 202105 (e1999b) and build it. Gitsm.needs_update() starts by calling Git.needs_update() which returns False, as the mirror tarball contains this revision. It then looks at the "nuggets" which are SRCREVs it has fetched before. The mirror tarball itself contains the nugget for e1999b as this has been built on the autobuilder, so needs_update return False, no more fetching is done, and the build proceeds to unpack. However, as part of the 202105 upgrade the URL of the cmocka submodule changed, and this new repository was never fetched. This means that unpack fails as one of the required git repositories isn't available. The nugget codepaths appear to be an attempt at optimising the fetch process, but have demonstratable failure cases. Just removing them entirely solves the edk2-firmware example, and all of the fetcher test cases still pass. (Bitbake rev: 51212507ce3f670ace9efb691c92887d66f7aaf8) Signed-off-by: Ross Burton <ross.burton@arm.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Poky
Poky is an integration of various components to form a pre-packaged build system and development environment which is used as a development and validation tool by the Yocto Project. It features support for building customised embedded style device images and custom containers. There are reference demo images ranging from X11/GTK+ to Weston, commandline and more. The system supports cross-architecture application development using QEMU emulation and a standalone toolchain and SDK suitable for 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 BSP layers which extend the systems capabilities in a modular way. Many layers are available and can be found through the layer index.
As an integration layer Poky consists of several upstream projects such as BitBake, OpenEmbedded-Core, Yocto documentation, the 'meta-yocto' layer which has configuration and hardware support components. These components are all part of the Yocto Project and OpenEmbedded ecosystems.
The Yocto Project has extensive documentation about the system including a reference manual which can be found at https://docs.yoctoproject.org/
OpenEmbedded is the build architecture used by Poky and the Yocto project. For information about OpenEmbedded, see the OpenEmbedded website.
Contribution Guidelines
The project works using a mailing list patch submission process. Patches should be sent to the mailing list for the repository the components originate from (see below). Throughout the Yocto Project, the README files in the component in question should detail where to send patches, who the maintainers are and where bugs should be reported.
A guide to submitting patches to OpenEmbedded is available at:
http://www.openembedded.org/wiki/How_to_submit_a_patch_to_OpenEmbedded
There is good documentation on how to write/format patches at:
https://www.openembedded.org/wiki/Commit_Patch_Message_Guidelines
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:
OpenEmbedded-Core (files in meta/, meta-selftest/, meta-skeleton/, scripts/):
- Git repository: https://git.openembedded.org/openembedded-core/
- Mailing list: openembedded-core@lists.openembedded.org
BitBake (files in bitbake/):
- Git repository: https://git.openembedded.org/bitbake/
- Mailing list: bitbake-devel@lists.openembedded.org
Documentation (files in documentation/):
- Git repository: https://git.yoctoproject.org/cgit/cgit.cgi/yocto-docs/
- Mailing list: docs@lists.yoctoproject.org
meta-yocto (files in meta-poky/, meta-yocto-bsp/):
- Git repository: http://git.yoctoproject.org/cgit/cgit.cgi/meta-yocto
- Mailing list: poky@lists.yoctoproject.org
If in doubt, check the openembedded-core git repository for the content you intend to modify as most files are from there unless clearly one of the above categories. Before sending, be sure the patches apply cleanly to the current git repository branch in question.