This article goes into detail about multiple areas of interest to contributors, which includes reviewers, developers, and integrators who each share an interest in guiding crosvm's direction.
Contributions to this project must be accompanied by a Contributor License Agreement (CLA). You (or your employer) retain the copyright to your contribution; this simply gives us permission to use and redistribute your contributions as part of the project. Head over to https://cla.developers.google.com/ to see your current agreements on file or to sign a new one.
You generally only need to submit a CLA once, so if you‘ve already submitted one (even if it was for a different project), you probably don’t need to do it again.
We use the Chromium issue tracker. Please use OS>Systems>Containers component.
The following is high level guidance for producing contributions to crosvm.
In the bin/ directory of the crosvm repository, there is the clippy script which lints the Rust code and the fmt script which will format the crosvm Rust code inplace.
The ./test_all script will use docker containers to run all tests for crosvm.
For more details on using the docker containers for running tests locally, including faster, iterative test runs, see ci/README.md.
To format all code, crosvm defers to rustfmt. In addition, the code adheres to the following rules:
The use statements for each module should be grouped in this order
stdcratecrosvm uses the remain crate to keep error enums sorted, along with the #[sorted] attribute to keep their corresponding match statements in the same order.
Since crosvm is one of Chromium OS projects, please read through Chrome OS Contributing Guide first. This section describes the crosvm-specific workflow.
We use Chromium Gerrit for code reviewing. All crosvm CLs are listed at the crosvm component.
Note: We don't accept any pull requests on the GitHub mirror.
If you have already set up the chromiumos repository and the repo command, you can simply create and upload your CL in the same way as other Chromium OS projects.
If you are not interested in other Chromium OS components, you can simply clone and contribute crosvm only. Before you make a commit locally, please set up Gerrit's Change-Id hook on your system.
$ git clone https://chromium.googlesource.com/chromiumos/platform/crosvm # Modify code and make a git commit with a commit message following this rule: # https://chromium.googlesource.com/chromiumos/docs/+/HEAD/contributing.md#Commit-messages $ git commit # Push your commit to Chromium Gerrit (https://chromium-review.googlesource.com/). $ git push origin HEAD:refs/for/main
Your change must be reviewed and approved by one of crosvm owners.
Once your change is reviewed, it will need to go through two layers of presubmit checks.
The review will trigger Kokoro to run crosvm specific tests. If you want to check kokoro results before a review, you can set ‘Commit Queue +1’ in gerrit to trigger a dry-run.
If you upload further changes after the you were given ‘Code Review +2’, Kokoro will automatically trigger another test run. But you can also always comment ‘kokoro rerun’ to manually trigger another build if needed.
When Kokoro passes, it will set Verified +1 and the change is ready to be sent to the ChromeOS commit queue by setting CQ+2.
Note: This is different from other ChromeOS repositories, where Verified +1 bit is set by the developers to indicate that they successfully tested a change. The Verified bit can only be set by Kokoro in the crosvm repository.
The commit queue will test your change on ChromeOS hardware, including high level end-to-end tests. Only if all of those pass, will the change be submitted.
Failures here will cause the commit queue to reject the change until it is re-added (CQ+2). Unfortunately, it is extremely common for false negatives to cause a change to get rejected, so be ready to re-apply the CQ+2 label if you're the owner of a ready to submit change.