Outreach Program Projects: Difference between revisions

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The Xen Project is a Linux Foundation collaborative project that develops the
The Xen Project is a Linux Foundation collaborative project that develops the
* Xen Hypervisor (for x86 and ARM) - the bulk of this page
* Xen Hypervisor (for x86 and ARM) - the bulk of this page. IRC channel #xendevel
* The XAPI toolstack (see [[#Mirage_OS]])
* Unikraft (see [[#Unikraft]]). IRC channel #unikraft
* Mirage OS (see [[#XAPI]])
* Mirage OS (see [[#Mirage_OS]]). IRC channel #mirage
* We also have some infrastructure, tooling and community related projects that run across '''all''' the sub-projects. These are slightly different from other projects, in terms of skills: see [[#Infra_and_Community]]
* We also have some infrastructure, tooling and community related projects that run across '''all''' the sub-projects. These are slightly different from other projects, in terms of skills: see [[#Infra_and_Community]]
The project also has excellent relationships with its upstreams (Linux Kernel, the BSDs, QEMU and other projects) and upstreams such as Linux distributions. This is reflected in the project list, which contains many interesting cross-project development projects for applicants.
The project also has excellent relationships with its upstreams (Linux Kernel, the BSDs, QEMU and other projects) and upstreams such as Linux distributions. This is reflected in the project list, which contains many interesting cross-project development projects for applicants.


=== Finding a project that fits you ===
=== Finding a project that fits you ===
This page lists Xen Project development projects for Outreachy (formerly the Outreach Program for Women) that can be picked up by anyone! If you're interesting in hacking Xen Project code and want to become a part of our friendly developer community this is the place to start! Ready for the challenge?
This page lists Xen Project development projects for Google Summer of Code and Outreachy (formerly the Outreach Program for Women). But projects can be picked up by anyone! If you're interesting in hacking Xen Project code and want to become a part of our friendly developer community this is the place to start! Ready for the challenge?


'''To work on a project:'''
'''To work on a project:'''
* Find a peer-reviewed project from below that looks interesting. If you do not find an interesting issue, you can also go to [http://xenorg.uservoice.com/forums/172169-xen-development/filters/top Xen UserVoice], pick a few projects from there and ask on [http://www.xenproject.org/help/mailing-list.html xen-devel@] whether the chosen project(s) would be suitable for Outreachy. Note that some of them may be too large or complex for Outreachy.
* Send an email to the relevant [http://www.xenproject.org/help/mailing-list.html mailing list] (see '''Developer Mailing Lists''') and let us know if you are interested in starting to work or applying on a specific project.
* Send an email to the relevant [http://www.xenproject.org/help/mailing-list.html mailing list] (see '''Developer Mailing Lists''') and let us know if you are interested in starting to work or applying on a specific project.
* Post your ideas, questions, RFCs to the relevant [http://www.xenproject.org/help/mailing-list.html mailing list] sooner than later so you can get comments and feedback.
* Post your ideas, questions, RFCs to the relevant [http://www.xenproject.org/help/mailing-list.html mailing list] sooner than later so you can get comments and feedback.
* '''Easy test projects''' to fulfil the [https://wiki.gnome.org/Outreachy#Make_a_Small_Contribution Make a Small Code Contribution Requirement]: An easy way to get started (and show that you can set up the Xen Development Environment, fix an issue, build and test Xen, submit a patch, etc.) is to address a suitable number of https://www.xenproject.org/help/contribution-guidelines.html#coverity Coverity Scan issues].
* An easy way to get started (and show that you can set up the Xen Development Environment, fix an issue, build and test Xen, submit a patch, etc.) is to address a suitable number of [https://www.xenproject.org/help/contribution-guidelines.html#coverity Coverity Scan issues].
* '''Small Contribution Requirement''': Outreachy requires that youfulfil the [https://wiki.gnome.org/Outreachy#Make_a_Small_Contribution Make a Small Code Contribution Requirement]. This is not strictly necessary for GSoC, but a small contribution to the project during the application period gives you an advantage
** Note that you will not be allowed to access Coverity scan logs. This is, because the Coverity service may discover security issues that have to be handled in compliance with our responsible disclosure practices as described in [http://www.xenproject.org/security-policy.html Xen Security Problem Response Process]. Thus, the full database of issues cannot simply be made public.
** You have to ask on [http://www.xenproject.org/help/mailing-list.html xen-devel@] for a set of suitable issues and later you may ask for [http://www.xenproject.org/help/contribution-guidelines.html access to coverity scan] or for a bug on [http://bugs.xenproject.org/xen/ /bugs.xenproject.org].


'''You have your own project idea: no problem!'''
'''You have your own project idea: no problem!'''
* If you have your own project idea, outline what you are trying to do on the mailing list. If you know the right list, post your project idea on [http://www.xenproject.org/help/mailing-list.html mailing list]. Failing that post on xen-devel and we can redirect you to the right list. Make sure you add '''Outreachy <round>''' to the subject line.
* If you have your own project idea, outline what you are trying to do on the mailing list. If you know the right list, post your project idea on [http://www.xenproject.org/help/mailing-list.html mailing list]. Failing that post on xen-devel and we can redirect you to the right list. Make sure you add '''Outreachy <round>''' or '''GSoC <year>''' to the subject line.


'''It is a good idea to ...'''<br>
'''It is a good idea to ...'''<br>
The Xen Project has also participated in the Gnome Outreach Program for Women (OPW) and Google Summer of Code (GSoC) in the past. One of the things we learned by participating in these programs is that you will be more successful, happier and get more out of participating in internship programs, if you do a bit of prep-work before writing an application. Here is some stuff you can do:
The Xen Project has participated in Outreachy and Google Summer of Code (GSoC) in the past. One of the things we learned by participating in these programs is that you will be more successful, happier and get more out of participating in internship programs, if you do a bit of prep-work before writing an application. Here is some stuff you can do:
* Contact your mentor early and get to know him or her
* Contact your mentor early and get to know him or her
* Start hanging out on our IRC channel. You can use the #xen-opw IRC channel on freenode.net for now
* Start hanging out on our IRC channels (#xendevel, #unikraft, #mirage)
* You may want to ask the mentor for a couple of small bitesize work-items (such as reviewing someones patch, a bitesize bug, ...) and start communicating on the relevant [http://www.xenproject.org/help/mailing-list.html mailing list]. That helps you become familiar with our development process, the mentor and other community members and will help you chose the right project and help you decide whether the Xen project is for you.
* You may want to ask the mentor for a couple of small bitesize work-items (such as reviewing someones patch, a bitesize bug, ...) and start communicating on the relevant [http://www.xenproject.org/help/mailing-list.html mailing list]. That helps you become familiar with our development process, the mentor and other community members and will help you chose the right project and help you decide whether the Xen project is for you.
* Note that quite a few Xen maintainers used to be GSoC participants once. Feel free to ask community dot manager at xenproject dot org to put you in touch with them if you have questions about their experience.
* Note that quite a few Xen maintainers used to be GSoC participants once. Feel free to ask community dot manager at xenproject dot org to put you in touch with them if you have questions about their experience.
* Any work you submit before applying for a project should be based on xen-unstable development tree, if the project is Xen Hypervisor and/or tools related. Linux kernel related patches should be based on upstream kernel.org Linux git tree (latest version). XAPI and Mirage OS patches should be based on the right codeline too. Check out the '''navigation by audience''' section on the left to find resources.
* Any work you submit before applying for a project should be based on xen-unstable development tree, if the project is Xen Hypervisor and/or tools related. Linux kernel related patches should be based on upstream kernel.org Linux git tree (latest version). Mirage OS patches should be based on the right codeline too. Check out the '''navigation by audience''' section on the left to find resources.


==== More resources ====
==== More resources ====
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== Projects completed in 2017 ==

{{ProjectComplete
|Project=Fuzzing Xen hypercall interface
|Acknowledgement=This project was completed by '''Felix Schmoll'''
|Refs=For more information see
* [https://blog.xenproject.org/2017/08/25/my-gsoc-experience-fuzzing-the-hypervisor/ My GSoC experience: Fuzzing the hypervisor]
* [https://lists.xen.org/archives/html/xen-devel/2017-08/msg01960.html Technical Summary of project]
* [https://summerofcode.withgoogle.com/archive/2017/projects/6343132106981376/ GSoC 2017]
|Date=8/02/2017
|Verified=8/2/2017
|Difficulty=Very high
|Contact=Wei Liu <wei.liu2@citrix.com>; make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=Strong C and ASM skills, good knowledge of GCC toolchain, good knowledge of GNU Make, good knowledge of fuzzing in general, good kernel programming and user space programming skills
|GSoC=Yes (accepted in 2017 - see https://summerofcode.withgoogle.com/dashboard/project/5585891117498368/overview/)
|Desc=The Xen Project has been using American Fuzzy Lop (AFL) for fuzzing and achieve useful results. Up until now we've only been able to adapt some Xen components to be fuzzed in a userspace program. There is untapped potential in using AFL (or other fuzzers) to fuzz hypercall interface. AFL (and other coverage guided fuzzers) requires feedback from the fuzzing target to mutate test cases. Xen does not yet have the ability to return precise execution path.

* Create a small domain or program to accept command from fuzzer, execute test case etc.
* Use GCC coverage support to give back precise execution path.
* Massage and feed the input back to fuzzer.


'''Related open source technologies and repositories''':
* [http://lcamtuf.coredump.cx/afl/ AFL home page] (and [http://lcamtuf.coredump.cx/afl/README.txt README])
* [http://events.linuxfoundation.org/sites/events/files/slides/AFL%20filesystem%20fuzzing%2C%20Vault%202016_0.pdf Shows how conceptually similar problems have been solved elsewhere]


|Outcomes=A system for fuzzing Xen hypercall interface.
}}

{{ProjectComplete
|Project=Share a page in memory from the VM config file
|Acknowledgement=This project was completed by '''Zhongze Liu'''
|Refs=For more information see
* [https://blog.xenproject.org/2017/08/29/my-gsoc-experience-allow-setting-up-shared-memory-regions-between-vms-from-xl-config-file/ My GSoC Experience: Allow Setting up Shared Memory Regions between VMs from xl Config File]
* [https://summerofcode.withgoogle.com/archive/2017/projects/5356246735519744/ GSoC 2017]
|Date=28/02/2017
|Verified=28/2/2017
|Difficulty=Average
|Contact=Stefano Stabellini <sstabellini@kernel.org>; Julien Grall <julien.grall@arm.com>; make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=Good C and kernel programming skills
|GSoC=Yes (2017)
|Desc=

Virtual machines use grant table hypercalls to setup a share page for inter-VMs communications. These hypercalls are used by all PV protocols today. However, very simple guests, such as baremetal applications, might not have the infrastructure to handle the grant table. This project is about setting up a shared page for inter-VMs communications directly from the VM config file. So that the guest kernel doesn't have to have grant table support to be able to communicate with other guests.

* introduce a new VM config option in xl
* allocate a page in memory and add it to the VM stage2 pagetable at a given address
* the page should be shareable with other virtual machines

|Outcomes=A new VM config file option is introduced to share a page in memory across multiple guests
}}


== List of peer reviewed Projects ==
== List of peer reviewed Projects ==
Line 122: Line 68:
=== Xen Hypervisor Userspace Tools ===
=== Xen Hypervisor Userspace Tools ===
{{project
{{project
|Project=golang bindings for libxl
|Project=golang consumer for the `xenlight` golang package
|Date=02/11/2016
|Date=28/01/2020
|Verified=25/1/2018
|Verified=17/02/2022
|Contact=George Dunlap <george.dunlap@citrix.com>; make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Contact=George Dunlap <george.dunlap@citrix.com>, IRC nick: gwd
|List=Make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate#
|IRC=#xendevel
|Difficulty=Straightforward
|Difficulty=Straightforward
|Skills=Familiarity with both C and the Go language
|Skills=Familiarity with the Go language
|Desc=The `xenlight` golang package consists of golang bindings for libxl, a robust library designed to be able to drive all necessary interaction with a Xen system; it's the library on which both xl and libvirt-xen are written.
|Desc=libxl is a robust library designed to be able to drive all necessary interaction with a Xen system; it's the library on which both xl and libvirt-xen are written. The Go programming language (http://www.golang.org) is a modern language spawned out of Google that aims to be a useful, small, typed language for user-level systems programming. As such, it is an obvious choice to write a control daemon or other system on top of libxl. A very rudimentary implementation was done by a previous outreach program participant; this would be carrying on that work. [https://xenproject.atlassian.net/browse/XEN-111 XEN-111] provides a list of function prototypes in libxl.h which have already been implemented. For those which have not been, these are listed in order of usefulness.


The golang bindings are nearing completion, and so this project would be to create an in-tree consumer of those bindings; partly as an example, partly to be useful. Ideas include:
The final goal of this work (which is more than a single internship or project) is to have a complete set of Go language bindings for libxl, along with a test suite to make sure that the interface works and is useable (as well as to serve as a template). One project / intership's worth of work would include implementing domain creation, and writing tools to automatically generate some Golang code from libxl's IDL.
|Outcomes=Extending the golang bindings to allow creation and manipulation of basic domains. Code to generate data structures from the libxl IDL rather than by hand.
|GSoC=yes
}}


* A simple `host status` daemon which would present information about the host: memory available, domains running, and so on
* A 'system stress tester', which would perform random operations (create / destroy / migrate / suspend VMs, create / destroy / migrate cpupools, &c) in quick succession to test the robustness of the system
* A re-implementation of the 'xl' command in Golang, suitable to be used as a drop-in replacement in our test system
* A 'wrapper' library to make creation of guests simple and straightforward, with a minimum of boilerplate


Applicants are encouraged to come up with their own ideas as well.
{{project
|Project=KDD (Windows Debugger Stub) enhancements
|Date=01/30/2014
|Verified=02/11/2016
|Contact=Paul Durrant <paul.durrant@citrix.com>; make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Difficulty=Medium
|Skills=C, Kernel Debuggers, Xen, Windows
|Desc=kdd is a Windows Debugger Stub for Xen hypervisor. It is OSS found under http://xenbits.xen.org/gitweb/?p=xen.git;a=tree;f=tools/debugger/kdd;h=fd82789a678fb8060cc74ebbe0a04dc58309d6d7;hb=refs/heads/master
kdd allows you to debug a running Windows virtual machine on Xen using standard Windows kernel debugging tools like WinDbg. kdd is an external debugger stub for the windows kernel.
Windows can be debugged without enabling the debugger stub inside windows kernel by using kdd. This is important for debugging hard to reproduce problems on Windows virtual machines that may not have debugging enabled.


|Outcomes=A useful project or library which exercises and demonstrates how to use the `xenlight` golang package.
Expected Results:
|GSoC=yes
# Add support for Windows 8.1 and 10 (x86, x64) to kdd
}}
# Add support for Windows Server 2012 to kdd
# Enhance kdd to allow WinDbg to write out usable Windows memory dumps (via .dump debugger extension) for all supported versions
# Produce a user guide for kdd on Xen wiki page


<br>
Nice to have: Allow kdd to operate on a Windows domain checkpoint file (output of xl save for e.g.)
|Outcomes=Code is submitted to xen-devel@xen.org for inclusion in the xen-unstable project.
|GSoC=yes}}


=== Xen Toolstack ===
=== Xen Toolstack ===

<br>


=== Xen Hypervisor ===
=== Xen Hypervisor ===


{{project
{{project
|Project=Fuzzing Xen hypercall interface (Part 2)
|Project=Xen on ARM: Performance Counters Virtualization
|Date=8/02/2017
|Date=01/02/2019
|Verified=22/1/2018
|Verified=01/28/2020
|Difficulty=Very high
|Difficulty=Hard
|Contact=Stefano Stabellini <sstabellini@kernel.org>, IRC nick: sstabellini; Julien Grall <julien@xen.org>, IRC nick: julieng
|Contact=Wei Liu <wei.liu2@citrix.com>; make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|List=Make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=Strong C and ASM skills, good knowledge of GCC toolchain, good knowledge of GNU Make, good knowledge of fuzzing in general, good kernel programming and user space programming skills
|IRC=#xendevel
|GSoC=Yes (accepted in 2017 - see https://summerofcode.withgoogle.com/dashboard/project/5585891117498368/overview/)
|Skills=Good C, assembly, and kernel programming skills
|Desc=The Xen Project has been using American Fuzzy Lop (AFL) for fuzzing and achieve useful results. Up until now we've only been able to adapt some Xen components to be fuzzed in a userspace program. There is untapped potential in using AFL (or other fuzzers) to fuzz hypercall interface. AFL (and other coverage guided fuzzers) requires feedback from the fuzzing target to mutate test cases. Xen does not yet have the ability to return precise execution path.

Note that part 1 of this project has been delivered via GSoC. For a status report of where things were left, see [https://lists.xen.org/archives/html/xen-devel/2017-08/msg01960.html this mail]. This project will cover a set of tasks labelled '''Future Work''' in [https://lists.xen.org/archives/html/xen-devel/2017-08/msg01960.html] to be agreed with the mentor.

'''Related open source technologies and repositories''':
* [https://lists.xen.org/archives/html/xen-devel/2017-08/msg01960.html Status of Part 1]
* [https://blog.xenproject.org/2017/08/25/my-gsoc-experience-fuzzing-the-hypervisor/ Experience report: My GSoC experience: Fuzzing the hypervisor]
* [http://lcamtuf.coredump.cx/afl/ AFL home page] (and [http://lcamtuf.coredump.cx/afl/README.txt README])
* [http://events.linuxfoundation.org/sites/events/files/slides/AFL%20filesystem%20fuzzing%2C%20Vault%202016_0.pdf Shows how conceptually similar problems have been solved elsewhere]


|Outcomes=A system for fuzzing Xen hypercall interface.
}}

{{project
|Project=Xen on ARM: create multiple guests from device tree
|Date=28/02/2017
|Verified=28/2/2017
|Difficulty=High
|Contact=Stefano Stabellini <sstabellini@kernel.org>; Julien Grall <julien.grall@arm.com>; make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=Good C and kernel programming skills
|GSoC=Yes
|GSoC=Yes
|Desc=Performance counters are a family of ARM registers used to measure performance. Today they are not virtualized by Xen, they are just trapped and implemented as read-as-zero/write-ignore, see xen/arch/arm/arm64/vsysreg.c and xen/arch/arm/arm64/vsysreg.c.
|Desc=Xen on ARM discovers the hardware via device tree: at boot time Xen parses a device tree binary passed by the bootloader. The binary contains information about the platform. It also contains extra information such as command line options for Xen and Dom0.


This project is about properly virtualizing these registers, so that guests can use them to measure their own performance. It involves saving and restoring the performance counters registers in Xen during VM context switch.
This project is about extending this extra information to include details about other unprivileged guests. Xen parses this additional info and creates the secondary guests directly at boot. Today, that's not possible and the user has to wait for dom0 to be fully booted and use `xl' to create additional guests.


|Outcomes=Xen guests can use performance counters.
* introduce new device tree bindings to create secondary guests at boot
* parse the new device tree nodes in Xen
* create secondary VMs directly from Xen at boot


|Outcomes=Xen on ARM is able to start multiple guests at boot time using information from device tree.
}}
}}






<br>
<br>


=== Mini-OS ===
=== Unikraft ===
'''Verified: 15/02/2021'''


Unikraft is a unikernel build system that enables developers to build
Mini-OS is a very small kernel being designed to run as a domU under Xen (either PV or PVH mode). It is primarily being used as the base for '''stubdoms''' e.g. to run grub, xenstore or qemu in paravirtualized mode in a dedicated domain. Mini-OS is multi-threaded and contains a basic memory management, some Xen backend drivers and a libc-like interface to applications which are linked directly with the kernel.

'''Related open source technologies and repositories''':
* [[Mini-OS]]
* [[Mini-OS-DevNotes|A tour of Mini-OS]]
* [http://xenbits.xen.org/gitweb/?p=mini-os.git;a=summary Mini-OS git tree]

Mini-OS is an excellent starting point for low-level kernel development: It is rather small and debugging it isn't very complicated as it is running as a Xen guest (you can look into it from the host and a complete test/debug/correction cycle may be well under one minute).

{{project
|Project=Adding Floating Point support to Mini-OS
|Date=28/02/2017
|Verified=28/2/2017
|Difficulty=Medium
|Contact=Juergen Gross <jgross@suse.com>; make sure you CC xen-devel@lists.xenproject.org AND minios-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=good C and ASM skills, knowledge of GCC toolchain, good kernel programming skills, good skills in understanding hardware documentation
|GSoC=Yes
|Desc=Currently Mini-OS has no support for using any Floating Point registers. This means no application needing more than one thread and using FP operations can be used with Mini-OS. Adding FP support to Mini-OS will remove that limitation.

* Create a small multi-thread test application for Mini-OS using FP registers to verify the lack of support.
* Add FP register saving/restoring when switching threads.
* Verify that the test application is working now.

|Outcomes=Full FP-support in Mini-OS.
}}

{{project
|Project=Add logging to a dom0 file support to Mini-OS
|Date=28/02/2017
|Verified=28/2/2017
|Difficulty=Medium
|Contact=Juergen Gross <jgross@suse.com>; make sure you CC xen-devel@lists.xenproject.org AND minios-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=good C, knowledge of GCC toolchain, good user and kernel programming skills
|GSoC=Yes
|Desc=The Xenstore domain is using Mini-OS as its kernel. The main lack of functionality compared to the Xenstore daemon in dom0 is the missing logging capability in order to find problems in e.g. strange behaving guests.

The easiest way to support such a logging capability would be the usage of a paravirtualized channel. Its frontend would connect to the file interface in Mini-OS, while the backend in dom0 should write the data sent via the channel to a file.

* Add the needed configuration items to libxl.
* Add the missing items to Mini-OS.
* Modify Xenstore domain configuration to make use of the feature.

'''Related open source technologies and repositories''':
* [[XenStore]] and [[XenStore_Reference]]

|Outcomes=Logging support in Mini-OS, especially for Xenstore domain.
}}

=== Unikraft ===
Unikraft is a Unikernel build system that enables developers to build
light-weight services starting from a highly customizable library base.
light-weight services starting from a highly customizable library base.
(for more information see [http://unikraft.org here]).
This library base includes core libraries which provide decomposed OS
functionality (e.g., schedulers, memory allocators, etc.) and enhanced
libraries that provide functionality to Unikernels that is often required
by applications (e.g., libC, network stacks). For more information please
checkout: [https://wiki.xenproject.org/wiki/Category:Unikraft]


We keep an up-to-date list of Unikraft-related projects as issues on github [https://github.com/unikraft/unikraft/issues?q=is%3Aissue+is%3Aopen+label%3Akind%2Fproject+-label%3Alifecycle%2Factive here]. If you're interested in one of them, or have project suggestions, please write us at <simon.kuenzer@neclab.eu> and <felipe.huici@neclab.eu>, cc minios-devel@lists.xenproject.org.
{{project
|Project=New Execution Targets
|Date=19/01/2018
|Verified=19/01/2018
|Difficulty=Medium
|Contact=Simon Kuenzer <simon.kuenzer@neclab.eu>; Felipe Huici <felipe.huici@neclab.eu> AND minios-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=Good C and ASM skills, good kernel programming skills, good understanding of operating system concepts, good skills in understanding hardware documentation
|GSoC=Yes
|Desc=Currently, Unikraft supports building images that can be executed as a virtual machine on [http://xenbits.xen.org/gitweb/?p=unikraft/unikraft.git;a=tree;f=plat/xen;hb=HEAD Xen] and [http://xenbits.xen.org/gitweb/?p=unikraft/unikraft.git;a=tree;f=plat/kvm;hb=HEAD KVM], and as an [http://xenbits.xen.org/gitweb/?p=unikraft/unikraft.git;a=tree;f=plat/linuxu;hb=HEAD ELF binary] within the Linux user space environment. Support for more execution targets is done by providing more platform libraries that can be chosen during build. The candidate is fairly free to choose a platform, perhaps based on familiarity or curiosity. In general, the wider the platform is used the better. Examples are:
* Bare-metal (preferred)
** ARM (e.g., raspberry Pi)(Diffculty: medium - hard)
** X86_64 (Diffculty: medium)
* Additional hypervisors
** VMware (Diffculty: hard)
** Microsoft Hyper-V (Diffculty: hard)
** bhyve (Diffculty: medium)
* …any others, we are open for suggestions!
|Outcomes=A new platform library that increases support for building Unikraft images for a new target
}}


<br>
{{project
|Project=FreeBSD's Network Stack Port
|Date=19/01/2018
|Verified=19/01/2018
|Difficulty=Medium
|Contact=Simon Kuenzer <simon.kuenzer@neclab.eu>; Felipe Huici <felipe.huici@neclab.eu> AND minios-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=Skills Needed: Good C skills, good understanding of operating system concepts, good skills in networking and network stacks
|GSoC=Yes
|Desc=Unikraft so far supports the lwIP (https://savannah.nongnu.org/projects/lwip/) network stack as initial support for TCP/IP. However, many Unikernel applications would benefit from a more feature-rich, better performing TCP/IP stack. The idea is to provide multiple TCP/IP implementations as libraries, allowing users to select and configure the most appropriate one for their Unikraft images. The task is to port BSD’s network stack as a Unikraft library (we choose it partly because it is license-compatible with Unikraft). Alternatively, this stack could be ported from OSv (http://osv.io/).
|Outcomes=BSD's TCP/IP stack as library for Unikraft
}}

{{project
|Project=High-level Language Support
|Date=19/01/2018
|Verified=19/01/2018
|Difficulty=Medium
|Contact=Simon Kuenzer <simon.kuenzer@neclab.eu>; Felipe Huici <felipe.huici@neclab.eu> AND minios-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=Skills Needed: Good C programming skills, good understanding of operating system concepts, understanding of high-level language runtime environments
|GSoC=Yes
|Desc=Supporting high-level or scripting languages with a Unikernel often requires porting the runtime environment. To name a few examples, such work was done with [https://mirage.io/ MirageOS] to run OCaml programs, [https://galois.com/project/halvm/ HalVM] to execute Haskell applications, and [https://github.com/sysml/minipython Mini-Python] to support Python scripts. The work consists of (1) choosing a popular high-level language, perhaps based on familiarity. (e.g., Java, JavaScript, Ruby, etc.) and (2) porting its runtime environment as a Unikraft library/application. The minimum target is to execute a simple high-level application with some console input and output.
|Outcomes=A new library/app for Unikraft that enables executing programs in a high-level language, at least with console input and output.
}}

{{project
|Project=Enhanced Profiling and Tracing Support
|Date=21/01/2018
|Verified=21/01/2018
|Difficulty=Medium
|Contact=Florian Schmidt <florian.schmidt@neclab.eu>; Simon Kuenzer <simon.kuenzer@necl.eu> AND minios-devel@lists.xenproject.org on all
communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=Skills Needed: Good C and ASM skills, good kernel programming skills, understanding of operating system concepts, good understanding of debugging techniques
|GSoC=Yes
|Desc=One problem for the acceptance of Unikernels is the limited debugging and profiling support. With Unikraft, we want to provide such support from early on. This work comprises (1) investigating popular tracing frameworks such as the Linux kernel [https://www.kernel.org/doc/Documentation/trace/ftrace.txt ftrace] / [https://www.kernel.org/doc/html/v4.13/core-api/tracepoint.html tracepoint API] and (2) implementing such a system for unikraft that allows tracing a Unikernel from the host OS.
|Outcomes=Enhanced Unikraft debugging library ([http://xenbits.xen.org/gitweb/?p=unikraft/unikraft.git;a=tree;f=lib/ukdebug;hb=HEAD libukdebug]) with fast profiling and tracing features
}}


=== Mirage OS ===
=== Mirage OS ===
Line 331: Line 135:
For Mirage OS, please check out the [http://canopy.mirage.io/tags/help%20needed list of Mirage OS projects where help is needed]. If you are interested in one of these projects, please e-mail [http://lists.xenproject.org/cgi-bin/mailman/listinfo/mirageos-devel mirageos-devel@lists.xenproject.org] and CC the mentor from the page (the project will contain a link to the mentor's GitHub account, which normally contains an email address and IRC information). You can also ask questions on the #mirage [http://xenproject.org/help/irc.html IRC] channel and usually find mentors on there.
For Mirage OS, please check out the [http://canopy.mirage.io/tags/help%20needed list of Mirage OS projects where help is needed]. If you are interested in one of these projects, please e-mail [http://lists.xenproject.org/cgi-bin/mailman/listinfo/mirageos-devel mirageos-devel@lists.xenproject.org] and CC the mentor from the page (the project will contain a link to the mentor's GitHub account, which normally contains an email address and IRC information). You can also ask questions on the #mirage [http://xenproject.org/help/irc.html IRC] channel and usually find mentors on there.


<br>
=== XAPI ===
=== XAPI ===


No projects at this stage.
No projects at this stage.

<br>


=== Infra and Community ===
=== Infra and Community ===
Line 339: Line 146:
We also have some infrastructure, tooling and community related projects that run across all the sub-projects. These are slightly different from other projects, in terms of skills and working with the community. Please check extra information below the project.
We also have some infrastructure, tooling and community related projects that run across all the sub-projects. These are slightly different from other projects, in terms of skills and working with the community. Please check extra information below the project.


<!--
{{project
|Project=Xen Code Review Dashboard
|Date=16/02/2016
|Verified=16/02/2016
|Difficulty=Medium
|Contact=Jesus M. Gonzalez-Barahona <jgb@bitergia.com>, Lars Kurth <lars.kurth@xenproject.org> and make sure you cc the xen-devel mailing list; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=SQL, Java/Javascript, HTML5/XML skills, basic software design knowledge (working with the mentors)
|GSoC=Yes
|Desc=The code review process in Xen is being analysed using [http://metricsgrimoire.github.io MetricsGrimoire] tools (correlating email based reviews with git commits in Xen Project trees to cover the entire workflow). The data is then stored in an SQL database and visualised using a Kibana based dashboard and some custom reports (e.g. [https://github.com/dicortazar/ipython-notebooks/blob/master/projects/xen-analysis/Code-Review-Metrics.ipynb]). The main objectives of this project is to extend the existing tools, to
# To produce a [http://github.com/grimoirelab/perceval Perceval-based] script to analyse the code review messages in Xen (instead of the original MLStats/CVSAnalY-based scripts). This would include taking the output of our current prototype scripts, and converting them into a more mature script, using information produced by Perceval.
# To enrich that information as is needed, based on existing [https://github.com/dicortazar/ipython-notebooks/blob/master/projects/xen-analysis/Code-Review-Metrics.ipynb custom reports], to produce the ElasticSearch indexes that we use for the dashboards.
# If time, to work with the Xen Project developer community on extending the dashboards themselves (note that this part may not be needed and depends on engagement with the developer communities' needs).
# If time, we could consider testing/extending the heuristics developed for Xen Project to work with other Linux-related projects, and maybe Linux itself.
All scripts, widgets and code developed as part of this project will be made available under open source licenses to either GitHub or a code repository hosted on [http://xenbits.xen.org/gitweb/ xenbits.xen.org/gitweb].


'''Related open source technologies and repositories''':
* [https://github.com/MetricsGrimoire MetricsGrimoire/MLStats (Git)]
* [https://github.com/grimoirelab/perceval Perceval (Git)]
* [https://github.com/elastic/kibana Kibana (Git)]
* [http://grimoirelab.github.io/ Grimoire Lab] and [https://github.com/GrimoireLab Grimoire Lab (Git)]
* [https://github.com/dicortazar/ipython-notebooks/blob/master/projects/xen-analysis/Code-Review-Metrics.ipynb Xen Project Custom Reports]
* [https://github.com/dicortazar/xen-code-review-analysis/tree/master Xen Specific Code]
* Screenshots of existing prototype dashboard
<gallery>
File:CodeReviewDashboard-StudiesA1.jpg
File:CodeReviewDashboard-StudiesB1.jpg
File:CodeReviewDashboard-StudiesC1.png
File:CodeReviewDashboard-StudiesD1.png
</gallery>
* [http://projects.bitergia.com/xen-project-dashboard/browser/data/db/ Test SQL database sets extracted from the Xen Project]
* [http://kibana-xen.bitergia.com/ Prototype Dashboard (work in progress)]
'''Further Information''':
* '''Small code contribution requirement''': Ask the mentors for a small task, based on an initial discussion.
* '''[http://xenproject.org/help/irc.html IRC]:''' #metrics-grimoire at freenet (mentors are jgbarah and lars_kurth)
* '''Mailing List:''' : [https://lists.libresoft.es/listinfo/metrics-grimoire metrics-grimoire@lists.libresoft.es] and CC xen-devel@lists.xenproject.org

|Outcomes=The final result is to enable the code review dashboard to add additional views, possibly augment the database and improve the heuristics of the existing prototype tools.
}}
-->

{{project
|Project=Add Centos Virt SIG Xen packages test to the CentOS CI loop
|Date=18/02/2016
|Verified=18/02/2016
|Difficulty=Easy
|Contact=George Dunlap <george.dunlap@citrix.com>; make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=Basic shell scripting
|GSoC=Yes
|Desc=The CentOS project has a continuous integration (CI) system running Jenkins, which can automatically run a set of tests when specific conditions are met, such as new versions of packages being available on the CentOS community build system (CBS). The CentOS Virtualization SIG ('Special Interest Group') produces Xen packages for CentOS 6 and 7, along with other related packages (such as libvirt). The goal of this project would be to add tests to this system to test the basic functionality of the Xen packages produced by the CentOS Virt SIG, helping to avoid regressions in released software.
|Outcomes=An appropriate array of tests for xen (and ideally libvirt) packages running in the CentOS CI loop.
}}

{{project
|Project=Code Standards Checking using clang-format
|Date=18/02/2016
|Verified=18/02/2016
|Difficulty=Easy
|Contact=Doug Goldstein <cardoe@cardoe.com>; make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Skills=clang-format, shell scripting (to skip files), potentially C++ to extend clang-format
|GSoC=Yes
|Desc=The Xen Project has a coding standard in place but like many projects the standard is only enforced through peer review. As such mistakes slip through and code is imported from other projects
which may not follow the same standard. The goal would be to come up with a script that can audit the code base as part of a CI loop for code style inconsistencies and potentially provide corrections. This project would start on one part of the tree and then move on through each component.
|Outcomes=A script that can be used to check some (or all of the tree) for code style standards violations.

'''Related open source technologies and repositories''':
* [http://xenbits.xen.org/gitweb/?p=xen.git;a=blob;f=CODING_STYLE Primary Coding Standard in Xen]
* [http://xenbits.xen.org/gitweb/?p=xen.git;a=blob;f=tools/libxl/CODING_STYLE LIBXL Coding Standard in Xen]
* [http://clang.llvm.org/ Information on clang] (also see [http://clang.llvm.org/docs/Tooling.html] & [http://clang.llvm.org/docs/ClangTools.html])
* [https://opensource.com/article/17/1/coding-style Using Clang-format to ensure clean, consistent code]
}}


<!--
{{project
{{project
|Project=Add more FreeBSD testing to osstest
|Project=Add more FreeBSD testing to osstest
|Date=10/02/2017
|Date=10/02/2017
|Verified=10/02/2017
|Verified=28/01/2019
|Difficulty=Moderate
|Difficulty=Moderate
|Contact=Roger Pau Monné <roger.pau@citrix.com>; Ian Jackson <ian.jackson@eu.citrix.com>; make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|Contact=Roger Pau Monné <roger.pau@citrix.com>, IRC nick: royger; Ian Jackson <ian.jackson@eu.citrix.com>, IRC nick: Diziet
|List=Make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
|IRC=#xendevel
|Skills=perl and shell (to write tests for osstest), FreeBSD system administration: pxe install, complete setup, build from sources, generate installer media.
|Skills=perl and shell (to write tests for osstest), FreeBSD system administration: pxe install, complete setup, build from sources, generate installer media.
|GSoC=Yes
|GSoC=Yes
|Desc=The current Xen Project test system only has minimal support for FreeBSD: it's able to test a FreeBSD guest, but it's not able to setup a FreeBSD host or perform a Xen compilation on FreeBSD. This project aims to solve this by providing better integration of FreeBSD into the Xen test system (osstest).
|Desc=The current Xen Project test system only has minimal support for FreeBSD: it's able to test a FreeBSD guest, but it's only able to partially setup a FreeBSD host or perform a Xen compilation on FreeBSD. This project aims to solve this by providing better integration of FreeBSD into the Xen test system (osstest).


First tasks will involve writing the necessary code so that osstest can setup a FreeBSD host and be able to build new FreeBSD host install media, so that we can start tracking FreeBSD upstream. Next steps will involve compiling Xen on FreeBSD and also generating FreeBSD guest install media, so that guests are also tracking upstream FreeBSD.
First tasks will involve writing support for building the 3rd-party packages needed for the Xen build using poudriere and creating a custom pkg repository. Next steps will involve building FreeBSD guest images from source and integrating with the xen-unstable flight.


Initial support for FreeBSD host has been merged into osstest, but it's incomplete.
An initial attempt at this can be found at https://lists.xenproject.org/archives/html/xen-devel/2015-02/msg00280.html The student can use part of this as a baseline if desired.
|Outcomes=Be able to setup a FreeBSD host from osstest tracking upstream FreeBSD sources and perform a Xen compilation on it. Also generate FreeBSD guest images and integrate them into osstest testing.
|Outcomes=Be able to setup a FreeBSD host from osstest tracking upstream FreeBSD sources and perform a Xen build on it. Also generate FreeBSD guest images and integrate them into osstest testing.
}}
}}
-->


<br>
<br>
Line 467: Line 208:


=== Choosing Projects ===
=== Choosing Projects ===
We have a bi-weekly mentor meeting overlooked by our program management team, which are a core team of 2-3 mentors and a program administrator. This group will work with mentors to ensure that project proposals are of good quality and whether mentors are engaging with the program management team and particpants in the weeks before the application period ends.
We have a bi-weekly mentor meeting overlooked by our program management team, which are a core team of 2-3 mentors and a program administrator. This group will work with mentors to ensure that project proposals are of good quality and whether mentors are engaging with the program management team and particpants in the weeks before the application period ends.

[[Category:Developers]]
[[Category:Index]]
[[Category:Project]]
[[Category:Internships]]
[[Category:Transient]] <!-- as if not maintained it becomes stale -->

Latest revision as of 16:06, 17 February 2022

The Xen Project is a Linux Foundation collaborative project that develops the

  • Xen Hypervisor (for x86 and ARM) - the bulk of this page. IRC channel #xendevel
  • Unikraft (see #Unikraft). IRC channel #unikraft
  • Mirage OS (see #Mirage_OS). IRC channel #mirage
  • We also have some infrastructure, tooling and community related projects that run across all the sub-projects. These are slightly different from other projects, in terms of skills: see #Infra_and_Community

The project also has excellent relationships with its upstreams (Linux Kernel, the BSDs, QEMU and other projects) and upstreams such as Linux distributions. This is reflected in the project list, which contains many interesting cross-project development projects for applicants.

Finding a project that fits you

This page lists Xen Project development projects for Google Summer of Code and Outreachy (formerly the Outreach Program for Women). But projects can be picked up by anyone! If you're interesting in hacking Xen Project code and want to become a part of our friendly developer community this is the place to start! Ready for the challenge?

To work on a project:

  • Send an email to the relevant mailing list (see Developer Mailing Lists) and let us know if you are interested in starting to work or applying on a specific project.
  • Post your ideas, questions, RFCs to the relevant mailing list sooner than later so you can get comments and feedback.
  • An easy way to get started (and show that you can set up the Xen Development Environment, fix an issue, build and test Xen, submit a patch, etc.) is to address a suitable number of Coverity Scan issues.
  • Small Contribution Requirement: Outreachy requires that youfulfil the Make a Small Code Contribution Requirement. This is not strictly necessary for GSoC, but a small contribution to the project during the application period gives you an advantage

You have your own project idea: no problem!

  • If you have your own project idea, outline what you are trying to do on the mailing list. If you know the right list, post your project idea on mailing list. Failing that post on xen-devel and we can redirect you to the right list. Make sure you add Outreachy <round> or GSoC <year> to the subject line.

It is a good idea to ...
The Xen Project has participated in Outreachy and Google Summer of Code (GSoC) in the past. One of the things we learned by participating in these programs is that you will be more successful, happier and get more out of participating in internship programs, if you do a bit of prep-work before writing an application. Here is some stuff you can do:

  • Contact your mentor early and get to know him or her
  • Start hanging out on our IRC channels (#xendevel, #unikraft, #mirage)
  • You may want to ask the mentor for a couple of small bitesize work-items (such as reviewing someones patch, a bitesize bug, ...) and start communicating on the relevant mailing list. That helps you become familiar with our development process, the mentor and other community members and will help you chose the right project and help you decide whether the Xen project is for you.
  • Note that quite a few Xen maintainers used to be GSoC participants once. Feel free to ask community dot manager at xenproject dot org to put you in touch with them if you have questions about their experience.
  • Any work you submit before applying for a project should be based on xen-unstable development tree, if the project is Xen Hypervisor and/or tools related. Linux kernel related patches should be based on upstream kernel.org Linux git tree (latest version). Mirage OS patches should be based on the right codeline too. Check out the navigation by audience section on the left to find resources.

More resources

Quick links to changelogs of the various Xen related repositories/trees: Please see XenRepositories wiki page!

Before to submit patches, please look at Submitting Xen Patches wiki page and the relevant Xen Project team page. This will contain more information.

If you have new ideas, suggestions or development plans let us know and we'll update this list!

Aspiring Participants

  • Please contact the mentor and CC the most appropriate mailing list
  • Get a bite-size task from the mentor before the application starts
  • If you feel comfortable with an idea, please put your name to an idea using the following format
{{project
...
|Review=(delete as addressed)
* {{Comment|~~~~:}} I am interested in this idea ... 
                    (note that you may also want to link to the e-mail thread with the mentor)
  • You will need to request write access to the wiki by filling out this form


Outreach Program Project Ideas

List of peer reviewed Projects

Xen Hypervisor Userspace Tools

golang consumer for the `xenlight` golang package

Date of insert: 28/01/2020; Verified: 17/02/2022; GSoC: yes
Technical contact: George Dunlap <george.dunlap@citrix.com>, IRC nick: gwd
Mailing list/forum for project: Make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate#
IRC channel for project: #xendevel
Difficulty: Straightforward
Skills Needed: Familiarity with the Go language
Description: The `xenlight` golang package consists of golang bindings for libxl, a robust library designed to be able to drive all necessary interaction with a Xen system; it's the library on which both xl and libvirt-xen are written.

The golang bindings are nearing completion, and so this project would be to create an in-tree consumer of those bindings; partly as an example, partly to be useful. Ideas include:

  • A simple `host status` daemon which would present information about the host: memory available, domains running, and so on
  • A 'system stress tester', which would perform random operations (create / destroy / migrate / suspend VMs, create / destroy / migrate cpupools, &c) in quick succession to test the robustness of the system
  • A re-implementation of the 'xl' command in Golang, suitable to be used as a drop-in replacement in our test system
  • A 'wrapper' library to make creation of guests simple and straightforward, with a minimum of boilerplate
Applicants are encouraged to come up with their own ideas as well.
Outcomes: A useful project or library which exercises and demonstrates how to use the `xenlight` golang package.


Xen Toolstack


Xen Hypervisor

Xen on ARM: Performance Counters Virtualization

Date of insert: 01/02/2019; Verified: 01/28/2020; GSoC: Yes
Technical contact: Stefano Stabellini <sstabellini@kernel.org>, IRC nick: sstabellini; Julien Grall <julien@xen.org>, IRC nick: julieng
Mailing list/forum for project: Make sure you CC xen-devel@lists.xenproject.org on all communications; tag mails with [GSoC] or [Outreachy] as appropriate
IRC channel for project: #xendevel
Difficulty: Hard
Skills Needed: Good C, assembly, and kernel programming skills
Description: Performance counters are a family of ARM registers used to measure performance. Today they are not virtualized by Xen, they are just trapped and implemented as read-as-zero/write-ignore, see xen/arch/arm/arm64/vsysreg.c and xen/arch/arm/arm64/vsysreg.c. This project is about properly virtualizing these registers, so that guests can use them to measure their own performance. It involves saving and restoring the performance counters registers in Xen during VM context switch.
Outcomes: Xen guests can use performance counters.


Unikraft

Verified: 15/02/2021

Unikraft is a unikernel build system that enables developers to build light-weight services starting from a highly customizable library base. (for more information see here).

We keep an up-to-date list of Unikraft-related projects as issues on github here. If you're interested in one of them, or have project suggestions, please write us at <simon.kuenzer@neclab.eu> and <felipe.huici@neclab.eu>, cc minios-devel@lists.xenproject.org.


Mirage OS

Several different projects (follow link)

For Mirage OS, please check out the list of Mirage OS projects where help is needed. If you are interested in one of these projects, please e-mail mirageos-devel@lists.xenproject.org and CC the mentor from the page (the project will contain a link to the mentor's GitHub account, which normally contains an email address and IRC information). You can also ask questions on the #mirage IRC channel and usually find mentors on there.


XAPI

No projects at this stage.


Infra and Community

We also have some infrastructure, tooling and community related projects that run across all the sub-projects. These are slightly different from other projects, in terms of skills and working with the community. Please check extra information below the project.




New Project Ideas

Please add new project ideas here, following

Conventions for Projects and Project Mentors

Rules and Advice for Adding Ideas

  • Be creative
  • Add projects into New Project Ideas or improve projects in Project Ideas that Need Review or more work through review comments.
  • Use the {{GSoC Project}} template to encode ideas on this page. Please read the Template Documentation before you do so.
  • Be specific: what do you want to be implemented; if at all possible provide an indication of size and complexity as described above to make it easier for an applicant to choose ideas
  • If you are willing to mentors those ideas, add your name and email to the idea.
  • Aspiring mentors should introduce themselves on the most appropriate Xen Project mailing list

Peer Review Goals

We strongly recommend and invite project proposers and project mentors to review each others proposals. When you review, please look out for

  • Can an intern get going and started with the information in the project description
  • Are any unstated assumptions in the proposal, is there undefined terminology, etc. in the proposal
  • Can the project completed in 3 months (assume that one month is needed for preparation)
  • Does the project meet Google Summer of Code goals, which are
    • Create and release open source code for the benefit of all
    • Inspire young developers to begin participating in open source development
    • Help open source projects identify and bring in new developers and committers
    • Provide interns the opportunity to do work related to their academic pursuits (think "flip bits, not burgers")
    • Give interns more exposure to real-world software development scenarios (e.g., distributed development, software licensing questions, mailing-list etiquette)

Peer Review Conventions

The {{GSoC Project}} template used to encode project listings, contains some review functionality. Please read the Template Documentation before you add a template, also please use the conventions below to make comments.

|Review=(delete as addressed)
* {{Comment|~~~~:}} Comment 1
* {{Comment|~~~~:}} Comment 2

Choosing Projects

We have a bi-weekly mentor meeting overlooked by our program management team, which are a core team of 2-3 mentors and a program administrator. This group will work with mentors to ensure that project proposals are of good quality and whether mentors are engaging with the program management team and particpants in the weeks before the application period ends.