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| We are looking for round 10 [:OPWSponsor:funding sponsors] and Linux kernel [:OPWMentor:mentors]. Please see the linked FAQ pages if you want to help out. | The application period for '''Round 13''' will start on September 12, 2016. It's too early to send patches to the outreachy kernel mailing list, but please consider working through the other parts of the tutorial if you are interested in applying. |
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| Welcome OPW applicants! Our [:OPWSponsor:round 10 sponsors] have generiously donated funds for internships for women, genderqueer, genderfluid, or genderfree people, and alumni from the [http://ascendproject.org/ Ascend Project] to work on the Linux kernel. The kernel is the most basic layer of the Linux operating system. It encompasses many things: hardware drivers, filesystems, security, task scheduling, and much more. | We are looking for round 13 [:OutreachySponsor:funding sponsors] and Linux kernel [:OutreachyMentor:mentors]. Please see the linked FAQ pages if you want to help out. Welcome Outreachy applicants! Our [:OutreachySponsor:round 13 sponsors] have generiously donated funds for internships for women, genderqueer, genderfluid, or genderfree people, and residents and nationals of the United States of any gender who are Black/African American, Hispanic/Latino, American Indian, Alaska Native, Native Hawaiian, or Pacific Islander to work on the Linux kernel. The kernel is the most basic layer of the Linux operating system. It encompasses many things: hardware drivers, filesystems, security, task scheduling, and much more. '''News''' This year, we ask that you send all patches to the appropriate staging driver maintainers, as well as to the outreachy mailing list. See [:FirstKernelPatch#submit_a_patch:Submit a patch] for more information. |
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| The application period for OPW Round 10 is February 17 to March 24. Please fill our your [https://live.gnome.org/OutreachProgramForWomen#Application_Process initial application] by March 24, and complete your initial kernel patch by March 24. Applicants that do not complete the first patch will not be considered for an internship. Please take a look at our [:OPWApply:application FAQ] for more info on how to fill our your initial application. | The application period for Outreachy Round 13 is September 12 to October 17. Please fill your [https://live.gnome.org/OutreachProgramForWomen#Application_Process application] by '''October 17''', and complete your kernel patch by '''October 17''' also (7pm UTC in both cases). Applicants that do not complete the first patch will not be considered for an internship. Please take a look at our [:OutreachyApply:application FAQ] for more info on how to fill out your application. |
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| * Join the #opw IRC channel on irc.gnome.org * Join the #kernel-opw IRC channel on irc.oftc.net * Read our [:OPWApply:instructions for applying], and apply by March 24. * Use our [:OPWfirstpatch:tutorial] to send in your first kernel patch by March 24. |
* Join the #outreachy IRC channel on irc.gnome.org * Join the #kernel-outreachy IRC channel on irc.oftc.net * Read our [:OutreachyApply:instructions for applying], and apply by October 17. * Use our [:Outreachyfirstpatch:tutorial] to send in your first kernel patch by October 17. |
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| Some projects may have small tasks you can complete as part of the application process. '''Do not''' start on these tasks until after you complete the [:OPWfirstpatch:first patch tutorial] and Greg Kroah-Hartman has accepted at least ten of your cleanup patches and two of your patchsets. In order to ensure applicants aren't working on the same task, we need your help in coordinating who is working on what task. Please see the [:OPWTasks:OPW tasks page] for details before starting on a task! | Some projects may have small tasks you can complete as part of the application process. '''Do not''' start on these tasks until after you complete the [:Outreachyfirstpatch:first patch tutorial] and Greg Kroah-Hartman has accepted at least ten of your cleanup patches and two of your patchsets. In order to ensure applicants aren't working on the same task, we need your help in coordinating who is working on what task. Please see the [:OutreachyTasks:Outreachy tasks page] for details before starting on a task! |
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| = Round 10 projects = More coming soon. Round 9 projects are available [:OPWRound9: here]. For each project, if you click on the proposer's name, you may find more information. |
= Round 13 projects = Previous projects, from round 12 projects are available [:OutreachyRound12:here]. For each project, if you click on the proposer's name, you may find more information. |
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| [http://coccinelle.lip6.fr Coccinelle] is a program matching and transformation tool for C code that has been used extensively in contributing to the Linux kernel, for both code evolutions and bug fixes. Coccinelle is driven by specifications, known as semantic patches, that use a notation based on C code, and are this fairly easy to develop. Around 40 semantic patches are included with the Linux kernel source code, in scripts/coccinelle, and are used in the continuous testing service provided by Intel. | Coccinelle is a program matching and transformation tool that has been extensively used for improving Linux kernel code. This project will involve using Coccinelle to address a security issue in the Linux kernel. |
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| The use of out of date APIs is confusing for people who need to understand the code, and requires the maintenance of excess code. The goal of this project is to use Coccinelle to replace out of date API uses in the Linux kernel with more modern equivalents. | The Linux kernel contains many data structures whose contents never change once they are initialized, many of which contain function pointers. Such structures that are modifiable at run time constitute a security risk, because an attacker may be able to overwrite the field value with a pointer to malicious code, that will then be executed with full kernel privileges. The first goal of this project is to use Coccinelle to insert const annotations on such structures to prevent runtime modfications. Some structures, however, cannot be made const, because they are initialized in several steps. In these cases, it may be possible to annotate the structure as {{{__ro_after_init}}}, if all of the initializations can take place during the init phase. The second goal is to add {{{__ro_after_init}}} where they are needed. This may requiring adding {{{__init}}} annotations on some code that is actually only needed during the init phase.line bash script. Please indicate in your application whether you are interested in this part of the project, however, interest in this part of the project is not a prerequisite for being selected as an intern. |
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| == Media Controller Virtual Driver == | More information about Coccinelle is available [http://coccinelle.lip6.fr/ here], including a [http://coccinelle.lip6.fr/papers/tutorial.pdf tutorial]. For some Coccinelle small tasks, click on the mentor name. |
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| ''Mentor:'': [:LaurentPinchart:Laurent Pinchart] | == IIO driver == ''Mentor:'': [:AlisonSchofield:Alison Schofield] and [:DanielBaluta:Daniel Baluta] |
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| The media subsystem has a kernel [http://lwn.net/Articles/607160/ driver] that emulates a V4L device in order to allow testing userspace applications without requiring hardware. We are, however, missing a driver that would emulate a [http://linuxtv.org/downloads/v4l-dvb-apis/media_controller.html Media Controller] device. Such a driver would be very useful to test handling of complex media pipelines in userspace applications. | A driver allows applications to communicate and control hardware devices. Each development cycle, driver changes account for more than a half of the total Linux kernel code changes. |
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| The goal of this project is to create a virtual Media Controller driver. No access to hardware is needed to perform this task, although a USB camera [http://ideasonboard.org/uvc/faq/#faq1 compatible with the USB Video Class] could be useful to first experiment with the Media Controller API. | The goal of this project is to write a driver for a sensor using the Industrial I/O interface. In the first part of the project you will get familiar with the hardware and the IIO subsystem then implement raw readings from the device. After upstreaming the code you will enhance the driver with advanced features such as support for buffered readings, power management and interrupts. The exact device will be decided when the internship starts. |
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| == Modernize Linux Wireless drivers == | We will provide you the hardware setup necessary to test the driver. If you are interested in this project please consider solving the [:IIO_tasks:IIO tasks]. |
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| ''Mentor'': [:JesSorensen: Jes Sorensen] | == nftables == ''Mentor:'': [:pablo:Pablo Neira Ayuso] |
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| The Linux wireless (WiFi) stack has migrated from the old obsolete WEXT API to the modern cfg80211/nl80211 API. The old WEXT API has been marked deprecated for years, but unfortunately a couple of drivers are still using it, making it impossible to remove the old code. | nftables provides a replacement for the very popular {ip,ip6,arp,eb}tables tools. nftables reuses most of the Netfilter components such as the existing hooks, connection tracking system, NAT, userspace queueing, logging among many other features. So we have only replaced the packet classification framework. nftables comes with a new userspace utility ''nft'' and the low-level userspace library ''libnftnl''. The goal will be to help finish the translation layer software that converts from the iptables syntax to nftables, complete some simple missing features and fixing bugs whenever possible. |
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| The goal of this project is to complete the conversion of the Orinoco wireless driver from using the WEXT API and make it a good cfg80211 citizen. | If you are interested in this project please consider solving any of the following tasks: |
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| == Full Dynamic Ticks == | * Request an account for the wiki.nftables.org page and help us improve the content. * Provide an iptables to nft translation via the iptables-translate utility. You can give a try to the following extensions: icmp, icmp6, rt. * Try to fix any of the existing nft bugs in bugzilla.netfilter.org. |
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| ''Mentors'': [:Frederic Weisbecker: Frederic Weisbecker], [:Preeti U Murthy: Preeti U Murthy] | For more information on nftables, please check: http://wiki.nftables.org |
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| CPUs have to be interrupted through periodic timers to initiate tasks such as update of CPUs'load and runtime of tasks, perform preemption of running tasks if necessary and load balancing to even out system wide load. But when CPUs are idle, none of these tasks is required to be performed as there is no load on them. So periodic timer interrupts can be stopped on idle CPUs. This improves power efficiency of the kernel to a good extent. Thus an infrastructure called "Tickless Idle" which disables periodic timer interrupts when CPUs are idle, was added to the 2.6.21 release of the Linux kernel. |
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| However some users required that periodic timer interrupts be disabled even on CPUs running single tasks. Typically high performance workloads (HPC) and real time tasks are performance critical and require to be run undisturbed as far as possible. For the benefit of such tasks, the Full Dynamic Ticks infrastructure was added to the 3.10 release of the Linux kernel. The goal of Full Dynamic Ticks is to enable CPUs to run in tickless mode as long as they are running single tasks. As a consequence it manages to isolate such CPUs to run performance critical user tasks without interruptions from the kernel. Over the months much effort has gone into making this stable. However there is more work to be done. |
== radix tree test suite == ''Mentors:'': [:RikvanRiel:Rik van Riel] and [:MatthewWilcox:Matthew Wilcox] |
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| The goal of this project is to tackle specific issues that are currently in way of running CPUs in Full Dynamic Tick mode effectively. | The radix tree test suite (found in tools/testing/radix-tree) is currently rather ad-hoc. It would benefit from someone sorting through it, looking for missing coverage (maybe use gcov), and adding tests to exercise the missing functionality. This project involves working primarily in user-space as the kernel code is pulled into userspace and compiled there. We could also use performance tests (Konstantin Khlebnikov recently posted patches that adds one performance test) The radix tree test suite was adapted from outside the kernel tree recently, and does not yet share much of the common test infrastructure, eg tools/include/ == radix tree __alloc_fd == ''Mentors:'': [:RikvanRiel:Rik van Riel] and [:MatthewWilcox:Matthew Wilcox] Currently sys_open() uses a linear search through a bitmap to find the first free file descriptor. This custom code could be replaced with the IDR interface. This replaces some custom code in the kernel with generic code (hopefully shrinking the size of the kernel), could result in some memory savings for processes with relatively few open files, and hopefully improve performance of workloads with very large numbers of open files. If you think you may be interested in this project, here are some small tasks to start with: * read how sys_open() currently finds the first open file descriptor, and allocates/resizes the file descriptor table * understand the IDR API * email Matthew and Rik a description of your findings, and a proposed project time line If you have any questions, please email Matthew and Rik. == radix tree PID allocation == ''Mentors:'': [:RikvanRiel:Rik van Riel] and [:MatthewWilcox:Matthew Wilcox] The PID allocator is a good match for the IDR API, but it currently uses its own custom allocator. Similar to the {{{__alloc_fd}}} project above, after understanding the IDR API, read how alloc_pid() works (paying particular attention to PID namespaces!) and come up with a project plan. == Project == ''Mentor:'': [:WikiName:Mentor names] Brief project description. |
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| * Join the [https://groups.google.com/forum/#!forum/opw-kernel opw-kernel mailing list] * Join the #opw IRC channel on irc.gnome.org * Join the #kernel-opw IRC channel on irc.oftc.net * Read our [:OPWApply:instructions for applying], and apply by October 31. * Use our [:OPWfirstpatch:tutorial] to send in your first kernel patch by October 31. * After you have sent several cleanup patches and at least one patchset, choose a [:OPWTasks:small task] to complete. |
* Join the [https://groups.google.com/forum/#!forum/outreachy-kernel outreachy-kernel mailing list] * Join the #outreachy IRC channel on irc.gnome.org * Join the #kernel-outreachy IRC channel on irc.oftc.net * Read our [:OutreachyApply:instructions for applying], and apply by October 17. * Use our [:Outreachyfirstpatch:tutorial] to send in your first kernel patch by October 17. * After you have 10 cleanup patches and at least two patchsets, choose some [:OutreachyTasks:small tasks] to complete. |
Outreachy (formerly FOSS Outreach Program for Women (OPW) and Project Ascend Alumni)
Please see the [https://www.gnome.org/outreachy/ Outreachy homepage] for an introduction to the program.
The application period for Round 13 will start on September 12, 2016. It's too early to send patches to the outreachy kernel mailing list, but please consider working through the other parts of the tutorial if you are interested in applying.
We are looking for round 13 [:OutreachySponsor:funding sponsors] and Linux kernel [:OutreachyMentor:mentors]. Please see the linked FAQ pages if you want to help out.
Welcome Outreachy applicants! Our [:OutreachySponsor:round 13 sponsors] have generiously donated funds for internships for women, genderqueer, genderfluid, or genderfree people, and residents and nationals of the United States of any gender who are Black/African American, Hispanic/Latino, American Indian, Alaska Native, Native Hawaiian, or Pacific Islander to work on the Linux kernel. The kernel is the most basic layer of the Linux operating system. It encompasses many things: hardware drivers, filesystems, security, task scheduling, and much more.
News This year, we ask that you send all patches to the appropriate staging driver maintainers, as well as to the outreachy mailing list. See [:FirstKernelPatch#submit_a_patch:Submit a patch] for more information.
How to apply
The application period for Outreachy Round 13 is September 12 to October 17. Please fill your [https://live.gnome.org/OutreachProgramForWomen#Application_Process application] by October 17, and complete your kernel patch by October 17 also (7pm UTC in both cases). Applicants that do not complete the first patch will not be considered for an internship. Please take a look at our [:OutreachyApply:application FAQ] for more info on how to fill out your application.
If you are interested in being a Linux kernel intern, please:
Join the [https://groups.google.com/forum/#!forum/outreachy-kernel outreachy-kernel mailing list]
- Join the #outreachy IRC channel on irc.gnome.org
- Join the #kernel-outreachy IRC channel on irc.oftc.net
Read our [:OutreachyApply:instructions for applying], and apply by October 17.
Use our [:Outreachyfirstpatch:tutorial] to send in your first kernel patch by October 17.
Participating Linux kernel projects
Applicants for all projects should have basic experience with C or C++ and boolean algebra. Optionally, we would love it if you have basic operating system knowledge, know your way around a Linux/UNIX command line, and/or know the revision system called git. Please note that these three skills can be learned during the internship.
Some projects may have small tasks you can complete as part of the application process. Do not start on these tasks until after you complete the [:Outreachyfirstpatch:first patch tutorial] and Greg Kroah-Hartman has accepted at least ten of your cleanup patches and two of your patchsets. In order to ensure applicants aren't working on the same task, we need your help in coordinating who is working on what task. Please see the [:OutreachyTasks:Outreachy tasks page] for details before starting on a task!
Round 13 projects
Previous projects, from round 12 projects are available [:OutreachyRound12:here]. For each project, if you click on the proposer's name, you may find more information.
Coccinelle
Mentor:: [:JuliaLawall:Julia Lawall]
Coccinelle is a program matching and transformation tool that has been extensively used for improving Linux kernel code. This project will involve using Coccinelle to address a security issue in the Linux kernel.
The Linux kernel contains many data structures whose contents never change once they are initialized, many of which contain function pointers. Such structures that are modifiable at run time constitute a security risk, because an attacker may be able to overwrite the field value with a pointer to malicious code, that will then be executed with full kernel privileges. The first goal of this project is to use Coccinelle to insert const annotations on such structures to prevent runtime modfications. Some structures, however, cannot be made const, because they are initialized in several steps. In these cases, it may be possible to annotate the structure as __ro_after_init, if all of the initializations can take place during the init phase. The second goal is to add __ro_after_init where they are needed. This may requiring adding __init annotations on some code that is actually only needed during the init phase.line bash script. Please indicate in your application whether you are interested in this part of the project, however, interest in this part of the project is not a prerequisite for being selected as an intern.
More information about Coccinelle is available [http://coccinelle.lip6.fr/ here], including a [http://coccinelle.lip6.fr/papers/tutorial.pdf tutorial]. For some Coccinelle small tasks, click on the mentor name.
IIO driver
Mentor:: [:AlisonSchofield:Alison Schofield] and [:DanielBaluta:Daniel Baluta]
A driver allows applications to communicate and control hardware devices. Each development cycle, driver changes account for more than a half of the total Linux kernel code changes.
The goal of this project is to write a driver for a sensor using the Industrial I/O interface. In the first part of the project you will get familiar with the hardware and the IIO subsystem then implement raw readings from the device. After upstreaming the code you will enhance the driver with advanced features such as support for buffered readings, power management and interrupts. The exact device will be decided when the internship starts.
We will provide you the hardware setup necessary to test the driver. If you are interested in this project please consider solving the [:IIO_tasks:IIO tasks].
nftables
Mentor:: [:pablo:Pablo Neira Ayuso]
nftables provides a replacement for the very popular {ip,ip6,arp,eb}tables tools. nftables reuses most of the Netfilter components such as the existing hooks, connection tracking system, NAT, userspace queueing, logging among many other features. So we have only replaced the packet classification framework. nftables comes with a new userspace utility nft and the low-level userspace library libnftnl. The goal will be to help finish the translation layer software that converts from the iptables syntax to nftables, complete some simple missing features and fixing bugs whenever possible.
If you are interested in this project please consider solving any of the following tasks:
- Request an account for the wiki.nftables.org page and help us improve the content.
- Provide an iptables to nft translation via the iptables-translate utility. You can give a try to the following extensions: icmp, icmp6, rt.
- Try to fix any of the existing nft bugs in bugzilla.netfilter.org.
For more information on nftables, please check: http://wiki.nftables.org
radix tree test suite
Mentors:: [:RikvanRiel:Rik van Riel] and [:MatthewWilcox:Matthew Wilcox]
The radix tree test suite (found in tools/testing/radix-tree) is currently rather ad-hoc. It would benefit from someone sorting through it, looking for missing coverage (maybe use gcov), and adding tests to exercise the missing functionality. This project involves working primarily in user-space as the kernel code is pulled into userspace and compiled there.
We could also use performance tests (Konstantin Khlebnikov recently posted patches that adds one performance test)
The radix tree test suite was adapted from outside the kernel tree recently, and does not yet share much of the common test infrastructure, eg tools/include/
radix tree __alloc_fd
Mentors:: [:RikvanRiel:Rik van Riel] and [:MatthewWilcox:Matthew Wilcox]
Currently sys_open() uses a linear search through a bitmap to find the first free file descriptor. This custom code could be replaced with the IDR interface. This replaces some custom code in the kernel with generic code (hopefully shrinking the size of the kernel), could result in some memory savings for processes with relatively few open files, and hopefully improve performance of workloads with very large numbers of open files.
If you think you may be interested in this project, here are some small tasks to start with:
- read how sys_open() currently finds the first open file descriptor, and allocates/resizes the file descriptor table
- understand the IDR API
- email Matthew and Rik a description of your findings, and a proposed project time line
If you have any questions, please email Matthew and Rik.
radix tree PID allocation
Mentors:: [:RikvanRiel:Rik van Riel] and [:MatthewWilcox:Matthew Wilcox]
The PID allocator is a good match for the IDR API, but it currently uses its own custom allocator. Similar to the __alloc_fd project above, after understanding the IDR API, read how alloc_pid() works (paying particular attention to PID namespaces!) and come up with a project plan.
Project
Mentor:: [:WikiName:Mentor names]
Brief project description.
Yeah, that sounds cool!
If you are interested in being a Linux kernel intern, please:
Join the [https://groups.google.com/forum/#!forum/outreachy-kernel outreachy-kernel mailing list]
- Join the #outreachy IRC channel on irc.gnome.org
- Join the #kernel-outreachy IRC channel on irc.oftc.net
Read our [:OutreachyApply:instructions for applying], and apply by October 17.
Use our [:Outreachyfirstpatch:tutorial] to send in your first kernel patch by October 17.
After you have 10 cleanup patches and at least two patchsets, choose some [:OutreachyTasks:small tasks] to complete.