Hooray! Thanks for your interest in working on the Linux kernel. The next step is to [:OPWApply:apply] to OPW, and use this tutorial to create your first patch to the Linux kernel.

Intro

If you run into any issues with this tutorial, please ask questions on the #kernel-opw IRC channel on irc.oftc.net, or on the [https://groups.google.com/forum/#!forum/opw-kernel opw-kernel mailing list].

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Contribution Instructions

PLEASE NOTE: DO NOT SEND YOUR FIRST PATCH TO THE MAIN LINUX MAILING LISTS!

Instead, send your patch to the [https://groups.google.com/forum/#!forum/opw-kernel opw-kernel mailing list].

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Resending patches

If you find a mistake in your initial patch submission, and you need to correct it, make sure to version your new patch as described in the previous section.

If your patch has not been responded to within three business days (not including weekend days), the mentors may have missed it, and you may want to resend it. Make sure to use RESEND in the subject line if the patch itself has not been changed (meaning no changes in the patch description or body). You can use the --subject-prefix argument to git format-patch to add RESEND, by running

git format-patch --subject-prefix="RESEND PATCH"

That command will create an email you can send with mutt (or your approved mail client) that will have a subject that looks like:

[RESEND PATCH] Foo: Fix these things

If your patch hasn't been responded to within a week, ping a mentor (or sarahsharp) on the IRC channel. Do not ping mentors immediately after sending patches. We know you're excited/worried about submitting your first patch, but mentors need to take time to properly respond and review patches.

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Tips for Applying to be an OPW Kernel intern

After you complete the first patch tutorial and get a patch accepted into the Linux kernel, you may wonder what to do next. We recommend getting 3-5 single cleanup patches accepted, and then moving on to create a patchset with several different cleanups for the same staging driver. Please limit your patchsets to no more than 10 patches, unless you've been told to break the patchset down further. Please try to limit your patches to no more than 100 to 200 lines total, to avoid mentors getting patch review fatigue. If you're bored and losing focus when you're tediously creating the patch, it's highly likely the mentors will get tired while reviewing it.

Once you've gotten 3-5 patchsets accepted, move onto exploring more complex tools, like sparse and coccinelle. Try to tackle some code refactoring, or take on a [:OPWTasks:small task]. Mentors will link to their task lists on the [:OPWIntro:OPW introduction page]. Mentors are more likely to pick you for their project if they see you tackling tasks from that project or asking questions about that project.

Tackling increasingly complex patches mean the OPW mentors will get a sense of how good a C programmer you are. It's very easy for beginner C programmers to do some of the more simple checkpatch cleanups, but it takes more skill to complete our mentor's small tasks, or sparse and coccinelle patches. You may find yourself trying to understand advanced C topics, such as [http://stackoverflow.com/questions/1665250/why-declare-a-variable-or-function-static-in-c/1665270#1665270 when to declare a function static]. If you are attempting silence a checkpatch.pl warning, and you don't understand what the warning message means, please ask on IRC or the mailing list before blindly trying to silence the warning. We value applicants that know when they need help, and we are happy to share knowledge and help you expand your skillset.

Please remember that we value consistently clean patches, so make sure to compile your code and ensure that no checkpatch errors or build warnings were added. Do this every single time for every patch revision, immediately before you send your patches out. We value applicants that learn fast enough to avoid making the same mistakes twice. It's a good practice to keep a log of improvements people have suggested for your previous patches, and double check that before submitting a new patch or patchset.

We look for applicants that can revise patches based on feedback from mentors. If you get feedback on a patch, change the code and send a revised patch. Don't just go onto the next patch. We value applicants that consistently send or revise patches every day, or every other day, rather than being sporatic about when patches are sent. Our best interns made the application process a part of their daily routine: prepare a patchset early in the day, go about their lives, and revise the patchset based on feedback received later in the day. Rinse and repeat.

We also value clear, concise communication. If you have a setup issue, tell us the exact failure mode, how to reproduce the failure, and what you've done to try and trouble shoot the failure. Please ensure that when you ask a question on IRC, you remain connected to the channel until someone answers your question. If no one answers in a couple hours, send the question to the mailing list.

We look for applicants that have a knack for seeking documentation and resources their own, while still knowing when to ask questions. If you have been stuck on a problem for more than a day, seek help! We love to see applicants ask questions on IRC and the mailing list, and we especially appreciate applicants that help each other out. Helping out someone who is struggling means you get to share your knowledge, and the act of writing down what you know will solidify that knowledge in your mind. It also shows the OPW mentors that you're learning new skills, and are willing to share that knowledge. Bonus points if you make a kernelnewbies account and correct or add knowledge to this wiki. To edit the wiki, create an account, and then send an email to the opw-kernel mailing list with the subject "[KERNEL NEWBIES ACCESS] username", where username is your kernel newbies username.

During the intern selection process, mentors will often already have a particular applicant in mind they want to pick. This applicant has often worked directly with the mentor, asked them questions, or sent them a detailed timeline for their project. Often times one particular project is very popular, because the mentor is highly responsive on the mailing list, and applicants like working with them. In that case, that project may be the first or second choice for many of the OPW applicants. Therefore, it is important to list at least four projects you are interested in, and make sure to work on small tasks from at least 2-3 OPW mentors.

There are also a few factors outside your control that may impact whether you are selected for an OPW internship. We try to ensure that the timezone difference between mentors and interns is acceptable. If the project requires specialized hardware, and it is difficult to get packages through customs in your country, you may not be selected for that project. An OPW internship is a full-time commitment, so we cannot accept you if you're working a full-time job, or taking more than one or two classes during the internship period. If there are many very good candidates, you may not be selected to be an OPW intern this round. We encourage you to apply next round, since you'll have a head start over the other candidates.

Good luck, future Linux kernel developers!