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* Make individual syscalls or groups of syscalls optional. See notes below for syscalls that can't currently be compiled out.
* Turn contig_page_data into .bss since it needs so little of itself initialized.
* Configure out writing time to the hardware clock (and in the process, compile out RTC_LIB)
* Compile out arch/x86/boot/early_serial_console
* Remove runtime extable sorting logic if CONFIG_BUILDTIME_EXTABLE_SORT
* Rip out the rest of kernel/smpboot.c if !CONFIG_SMP
 * Make individual syscalls or groups of syscalls optional. See notes below for syscalls that can't currently be compiled out.
 * Turn contig_page_data into .bss since it needs so little of itself initialized.
 * Configure out writing time to the hardware clock (and in the process, compile out RTC_LIB)
 * Compile out arch/x86/boot/early_serial_console
 * Remove runtime extable sorting logic if CONFIG_BUILDTIME_EXTABLE_SORT
 * Rip out the rest of kernel/smpboot.c if !CONFIG_SMP
Line 104: Line 104:
* Make ptrace optional.
* Modify GCC's "section" attribute to support specifying different sections for initialized (.data) and uninitialized (.bss) data, and use that to put uninitialized __initdata or per-CPU data into .bss. (This will require very detailed exploration of the toolchain, Linux's linker scripts, and similar.)
* Rip out more of the per-CPU infrastructure when CONFIG_SMP=n
* Support configuring out kswapd.
* Make the kernel's entire random number infrastructure optional.
* Compile out mm/vmstat (need to stub out bits that obtain statistics used by other bits of the kernel)
 * Make ptrace optional.
 * Modify GCC's "section" attribute to support specifying different sections for initialized (.data) and uninitialized (.bss) data, and use that to put uninitialized __initdata or per-CPU data into .bss. (This will require very detailed exploration of the toolchain, Linux's linker scripts, and similar.)
 * Rip out more of the per-CPU infrastructure when CONFIG_SMP=n
 * Support configuring out kswapd.
 * Make the kernel's entire random number infrastructure optional.
 * Compile out mm/vmstat (need to stub out bits that obtain statistics used by other bits of the kernel)

FOSS Outreach Program for Women (OPW)

Please see the FOSS Outreach Program for Women homepage for an introduction to the program.

We are looking for round 8 funding sponsors and Linux kernel mentors. Please see the linked FAQ pages if you want to help out.

Welcome OPW applicants! Our round 8 sponsors have generiously donated funds for internships for women and genderqueer/genderfluid people 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.

How to apply

The application period for OPW Round 8 is Feb 25th to March 19th. Please fill our your initial application and complete your initial kernel patch by March 19th. Applicants that do not complete the first patch will not be considered for an internship. Please take a look at our application FAQ for more info on how to fill our your initial application. Applicants will be notified on April 21st if they have been accepted.

If you are interested in being a Linux kernel intern, please:

We also encourage all OPW applicants that are students to also apply to Google Summer of Code, and in particular the Linux Foundation projects. The Google Summer of Code projects are separate from the projects listed below, so you will need to work on applications for both programs.

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.

Round 8 (May to August 2014) projects:

Coccinelle

Coccinelle is a program matching and transformation tool for C code that has been used extensively in contributing to the Linux kernel, for both 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.

The goal of this internship is to help build up the set of semantic patches that are included in the Linux kernel. This will involve primarily hardening semantic patches that have been developed previously, and putting them in the form used in the semantic patches Linux kernel. There is ample opportunity to contribute patches to Linux source code as part of the semantic patch hardening process.

Mentor: Julia Lawall

Linux-Kernel RCU

Potential projects include:

  1. Automatically Locate RCU Abuses

  2. Inline rcu_read_lock()

  3. Add kmem_cache_free_rcu()

  4. Validate RCU Algorithms

  5. Automate Testing of RCU CPU Stall Warnings

  6. Port RCU's KVM Scripts

  7. Miscellaneous Fixes to RCU

For more details on each project, please see this page.

Mentor: Paul E. McKenney < paulmck@linux.vnet.ibm.com >

ath5k

Ath5k is a completely FOSS wireless driver for Atheros based wireless chipset versions AR5xxx in the Linux Kernel. The hardware is old but the driver is still heavily used on academia/research and on various modern applications (e.g. 802.11p).

Some time ago Adrian Chadd released code on AR5513 (the Atheros HAL -Hardware Access Layer- for that chipset), it's a chipset able to do 802.11a/b/g with a smart antenna/dual PHY design. The goal of this project is to port this code on ath5k and add support for AR5513. In the process you'll get familiar with the low level parts of wireless cards, the inner workings of a device driver, the related subsystems and the challenges we face when playing with hardware.

An additional potential project is to implement 802.11 power saving modes for existing devices, enabling more efficient use in battery-powered stations such as laptops. Some preliminary patches have been already posted, but they need cleanup, functional changes, and validation. The interested intern would study the 802.11 specification, relevant parts of mac80211, the provisional patches, and possibly other related drivers such as ath9k to create a working, upstreamable implementation of power saving.

Mentors: Nick Kossifidis, Adrian Chadd, Bob Copeland

nftables

nftables is a new firewalling framework available since the Linux kernel 3.13. It includes new userspace libraries and utilities that aim to replace the popular {ip,ip6,arp,eb}tables utilities.

The goal of this internship is to help to improve nftables, this includes:

  1. chase bugs and fix them. We already have a good bunch in the Netfilter's bugzilla website.

  2. implement an automated testing infrastructure for nftables that would help to catch regressions.

  3. help us implement some of the missing features.

Please, read the nftables HOWTO to get familiarized with the new software.

Mentor: Pablo Neira Ayuso

Kernel tinification (for next round)

Over time, the Linux kernel has grown far more featureful, but it has also grown significantly larger, even with all the optional features turned off. I'd like to reverse that trend, making the kernel much smaller, to enable ridiculously small embedded applications and other fun uses.

In this project, you'll start from "make allnoconfig", and then try to shrink the kernel even further. You'll learn how to work with the kernel configuration system, Kconfig, and use scripts/bloat-o-meter to measure the size impact of a change.

This is a highly incremental project: each feature you make optional or kernel component you shrink will mostly stand alone, and you can develop and submit each change independently.

Some of these tinification goals will work well during the application period; others will require a substantial time investment, and will primarily make sense during the full internship.

Before working on any of these, especially during the application period, you should send a quick note to the OPW kernel mailing list to coordinate, and avoid duplicated effort.

All patches submitted for this project should include the output of "scripts/bloat-o-meter", run on the old and new "vmlinux" binaries. That will tell you exactly how much space the change saved.

Almost all new Kconfig options added for this project should depend on CONFIG_EMBEDDED.

Goals that will work either during the internship or during the application period:

  • Make individual syscalls or groups of syscalls optional. See notes below for syscalls that can't currently be compiled out.

  • Turn contig_page_data into .bss since it needs so little of itself initialized.

  • Configure out writing time to the hardware clock (and in the process, compile out RTC_LIB)

  • Compile out arch/x86/boot/early_serial_console

  • Remove runtime extable sorting logic if CONFIG_BUILDTIME_EXTABLE_SORT

  • Rip out the rest of kernel/smpboot.c if !CONFIG_SMP

Goals that should wait until a full internship:

  • Make ptrace optional.

  • Modify GCC's "section" attribute to support specifying different sections for initialized (.data) and uninitialized (.bss) data, and use that to put uninitialized initdata or per-CPU data into .bss. (This will require very detailed exploration of the toolchain, Linux's linker scripts, and similar.)

  • Rip out more of the per-CPU infrastructure when CONFIG_SMP=n

  • Support configuring out kswapd.

  • Make the kernel's entire random number infrastructure optional.

  • Compile out mm/vmstat (need to stub out bits that obtain statistics used by other bits of the kernel)

List of syscalls that the kernel doesn't currently support compiling out: sys_access sys_adjtimex sys_alarm sys_brk sys_capget sys_capset sys_chdir sys_chmod sys_chown sys_chroot sys_clock_adjtime sys_clock_getres sys_clock_gettime sys_clock_nanosleep sys_clock_settime sys_clone sys_close sys_creat sys_dup sys_dup2 sys_dup3 sys_execve sys_exit sys_exit_group sys_faccessat sys_fadvise64 sys_fadvise64_64 sys_fallocate sys_fchdir sys_fchmod sys_fchmodat sys_fchown sys_fchownat sys_fcntl sys_fcntl64 sys_fdatasync sys_fgetxattr sys_flistxattr sys_fork sys_fremovexattr sys_fsetxattr sys_fstat sys_fstat64 sys_fstatat64 sys_fstatfs sys_fstatfs64 sys_fsync sys_ftruncate sys_ftruncate64 sys_futimesat sys_getcpu sys_getcwd sys_getdents sys_getdents64 sys_getegid sys_geteuid sys_getgid sys_getgroups sys_gethostname sys_getitimer sys_getpgid sys_getpgrp sys_getpid sys_getppid sys_getpriority sys_getresgid sys_getresuid sys_getrlimit sys_getrusage sys_getsid sys_gettid sys_gettimeofday sys_getuid sys_getxattr sys_ioctl sys_ioperm sys_kill sys_lchown sys_lgetxattr sys_link sys_linkat sys_listxattr sys_llistxattr sys_llseek sys_lremovexattr sys_lseek sys_lsetxattr sys_lstat sys_lstat64 sys_mkdir sys_mkdirat sys_mknod sys_mknodat sys_mmap_pgoff sys_mount sys_munmap sys_nanosleep sys_newfstat sys_newfstatat sys_newlstat sys_newstat sys_newuname sys_ni_syscall sys_nice sys_old_getrlimit sys_old_mmap sys_old_readdir sys_old_select sys_oldumount sys_olduname sys_open sys_openat sys_pause sys_personality sys_pipe sys_pipe2 sys_pivot_root sys_poll sys_ppoll sys_prctl sys_pread64 sys_preadv sys_prlimit64 sys_pselect6 sys_ptrace sys_pwrite64 sys_pwritev sys_read sys_readahead sys_readlink sys_readlinkat sys_readv sys_reboot sys_removexattr sys_rename sys_renameat sys_renameat2 sys_restart_syscall sys_rmdir sys_rt_sigaction sys_rt_sigpending sys_rt_sigprocmask sys_rt_sigqueueinfo sys_rt_sigsuspend sys_rt_sigtimedwait sys_rt_tgsigqueueinfo sys_sched_get_priority_max sys_sched_get_priority_min sys_sched_getaffinity sys_sched_getattr sys_sched_getparam sys_sched_getscheduler sys_sched_rr_get_interval sys_sched_setaffinity sys_sched_setattr sys_sched_setparam sys_sched_setscheduler sys_sched_yield sys_select sys_sendfile sys_sendfile64 sys_set_tid_address sys_setdomainname sys_setfsgid sys_setfsuid sys_setgid sys_setgroups sys_sethostname sys_setitimer sys_setns sys_setpgid sys_setpriority sys_setregid sys_setresgid sys_setresuid sys_setreuid sys_setrlimit sys_setsid sys_settimeofday sys_setuid sys_setxattr sys_sgetmask sys_sigaction sys_sigaltstack sys_signal sys_sigpending sys_sigprocmask sys_sigsuspend sys_splice sys_ssetmask sys_stat sys_stat64 sys_statfs sys_statfs64 sys_stime sys_symlink sys_symlinkat sys_sync sys_sync_file_range sys_sync_file_range2 sys_syncfs sys_sysctl sys_sysinfo sys_tee sys_tgkill sys_time sys_timer_create sys_timer_delete sys_timer_getoverrun sys_timer_gettime sys_timer_settime sys_times sys_tkill sys_truncate sys_truncate64 sys_umask sys_umount sys_uname sys_unlink sys_unlinkat sys_unshare sys_ustat sys_utime sys_utimensat sys_utimes sys_vfork sys_vhangup sys_vmsplice sys_wait4 sys_waitid sys_waitpid sys_write sys_writev

(Note to mentors and prospective applicants: Josh plans to present this list at Linux Kernel Summit, and may add, remove, or edit items on this list based on feedback obtained there.)

Mentor:: Josh Triplett

Yeah, that sounds cool!

If you are interested in being a Linux kernel intern, please:

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last edited 2014-08-01 22:43:32 by JoshTriplett