HOWTO – Mailing lists with Mailman on Ubuntu 10.04

GNU mailman logoBootlin is not in the system administration business (we offer free and open-source solutions for embedded systems), but we do our best to share whatever experience we acquire, and whatever code we produce.

We configured a KVM virtual machine to run our mailing lists, and we used Ubuntu 10.04, the long term support (LTS) version. Here are instructions based on this experience. You could also use the same instructions to install Ubuntu 10.04 on a tiny, low power ARM board. And if you wish to use a more recent version of Ubuntu, I expect the steps to be very similar.

Here we assume that your domain is example.com and that you install your mailing list software on lists.example.com. It is indeed a good idea to install your mailing list software on a different server. This way, you won’t mess up with your main web and mail servers. Not having CGI scripts running on it will also keep your main mail server more secure.

Install packages

Install the Apache web server. It will allow administrators to configure and manage the lists, and users to subscribe, unsubscribe and tune their subscription settings.

sudo apt-get install apache2

For e-mail delivery, I chose the Postfix MTA (Mail Transport Agent). Exim would have been a good solution too, but I am more familiar with Postfix, which is already in use on our main mail server.

sudo apt-get install postfix

Choose the Internet site option.

Now install the mailman package:

sudo apt-get install mailman

Select the languages that you want your mailing list interfaces to support. I chose English and French for the moment. To add more languages later, run:

sudo dpkg-reconfigure mailman

Configure the Apache web server

First copy the sample Apache configuration file provided by the mailman package:

cp /etc/mailman/apache.conf /etc/apache2/sites-available/mailman

Now, in /etc/apache2/sites-available/mailman, enable short URLs by enabling:

ScriptAlias /mailman/ /usr/lib/cgi-bin/mailman/

Also modify /etc/mailman/mm_cfg.py:

DEFAULT_URL_PATTERN = 'http://%s/mailman/'

The last step is to enable your mailman site in Apache:

sudo a2ensite mailman
sudo /etc/init.d/apache2 restart

You should now have a new symbolic link in /etc/apache2/sites-enabled/.

Check that the Mailman website works by opening your mailing lists home page: http://lists.example.com/mailman/listinfo. It should look like https://lists.bootlin.com/mailman/listinfo.

Configure postfix

Enable the following line in /etc/mailman/mm_cfg.py:

MTA='Postfix'

Once the MTA is configured, generate Mailman specific aliases for Postfix:

sudo /usr/lib/mailman/bin/genaliases

Now, you need to configure Postfix through its main.cf file. A convenient way to do this is to run the below commands:

sudo postconf -e 'relay_domains = lists.example.com'
sudo postconf -e 'transport_maps = hash:/etc/postfix/transport'
sudo postconf -e 'mailman_destination_recipient_limit = 1'
sudo postconf -e 'alias_maps = hash:/etc/aliases, hash:/var/lib/mailman/data/aliases'

Also add the following line to /etc/postfix/transport:

lists.bootlin.com      mailman:

and run:

sudo postmap -v /etc/postfix/transport

You won’t have any mail delivery if you forget. I struggled for a few hours before I realized I forgot this setting.

Now, set correct file ownership:

sudo chown root:list /var/lib/mailman/data/aliases
sudo chown root:list /etc/aliases

For logging and debugging e-mail delivery, I recommend to install the sysklogd package. Without it, you won’t have any mail.info, mail.warn and mail.err files in /var/mail/.

To install this package, enable the universe repository if needed (uncomment the lines with universe in the /etc/apt/sources.list file), and run:

sudo apt-get update
sudo apt-get install sysklogd

To avoid having two mail.info and mail.log files with identical contents, edit /etc/syslog.conf and remove the below line:

mail.*                          -/var/log/mail.log

Also create a /etc/logrotate.d/mail file to rotate logs, as in the below example:

/var/log/mail.* {
        daily
        size 10M
        rotate 4
        compress
        missingok
        notifempty
        create 640 root adm
}

Last but not least, restart Postfix:

/etc/init.d/postfix restart

At this point, a good idea is to check that mail delivery works:

sudo apt-get install bsd-mailx
mailx alice@example.com
Subject: test
test
.
Cc: 

Note: that’s the line containing only a dot character that allows to terminate the message.

If the receipient doesn’t receive this message, there is an issue in the way your mail server is configured. This could be because the firewall doesn’t allow connections to outside machines through tcp port 25. Anyway, look at the logs in /var/log/mail.* to get a clue. There is no point going on in this howto until you get this fixed.

Creating the mailman site list

Mailman needs a so-called “site list”, which is the list from which password reminders and such are sent out from. The default name for this list list mailman, though you can change this through the MAILMAN_SITE_LIST setting in /etc/mailman/mm_cfg.py.

To create this list, run:

sudo newlist mailman

You will have to answer a few questions like:

Enter the email of the person running the list: postmaster@example.com
Initial newsletter password: xxx
Hit enter to notify newsletter owner...

Choose the password carefully, as crackers will be able to highjack your mailing list if it is too easy to guess.

The next required step is to add the list aliases to /etc/aliases:

# mailman mailing list
mailman:              "|/var/lib/mailman/mail/mailman post mailman"
mailman-admin:        "|/var/lib/mailman/mail/mailman admin mailman"
mailman-bounces:      "|/var/lib/mailman/mail/mailman bounces mailman"
mailman-confirm:      "|/var/lib/mailman/mail/mailman confirm mailman"
mailman-join:         "|/var/lib/mailman/mail/mailman join mailman"
mailman-leave:        "|/var/lib/mailman/mail/mailman leave mailman"
mailman-owner:        "|/var/lib/mailman/mail/mailman owner mailman"
mailman-request:      "|/var/lib/mailman/mail/mailman request mailman"
mailman-subscribe:    "|/var/lib/mailman/mail/mailman subscribe mailman"
mailman-unsubscribe:  "|/var/lib/mailman/mail/mailman unsubscribe mailman"

In addition to delivering e-mail to the mailing lists, these aliases also allow to subscribe and unsubscribe by writing to special e-mail addresses.

You also need to run the newaliases command, without which there is no e-mail delivery:

sudo newaliases
sudo /etc/init.d/postfix restart
sudo /etc/init.d/mailman restart

Look at the /var/log/mailman/error file for potential issues.

Create regular mailing lists

Regular mailing lists are created in the same way as above: Assuming you want to create a newsletter mailing list. You will need run:

sudo newlist newsletter

Add your new mailing list to /etc/aliases:

# newletter mailing list
newsletter:              "|/var/lib/mailman/mail/mailman post newsletter"
newsletter-admin:        "|/var/lib/mailman/mail/mailman admin newsletter"
newsletter-bounces:      "|/var/lib/mailman/mail/mailman bounces newsletter"
newsletter-confirm:      "|/var/lib/mailman/mail/mailman confirm newsletter"
newsletter-join:         "|/var/lib/mailman/mail/mailman join newsletter"
newsletter-leave:        "|/var/lib/mailman/mail/mailman leave newsletter"
newsletter-owner:        "|/var/lib/mailman/mail/mailman owner newsletter"
newsletter-request:      "|/var/lib/mailman/mail/mailman request newsletter"
newsletter-subscribe:    "|/var/lib/mailman/mail/mailman subscribe newsletter"
newsletter-unsubscribe:  "|/var/lib/mailman/mail/mailman unsubscribe newsletter"

Then, run the usual commands:

sudo newaliases
sudo /etc/init.d/postfix restart
sudo /etc/init.d/mailman restart

Configuring your lists

The easiest way to configure your lists and add members is to open the http://lists.example.com.com/mailman/listinfo URL with a browser.

A few things are also possible from the command line. For example, you can add a member as follows:

echo "alice@example.com" > /tmp/foo
sudo add_members -r /tmp/foo newsletter

Enabling archives

Default file permissions are not completely ready to support mailing list archives:

sudo chown -R root:list /var/lib/mailman/archives
sudo chmod o+rX /var/lib/mailman/archives/private

The second line allows the webserver to access the archives. Note that these settings were forgotten in the official Ubuntu documentation.

Settings for newsletter mailing lists

At Bootlin, we also use Mailman to deliver our newsletters. Mailman provides recipients with an easy mechanism to subscribe by themselves and unsubscribe whenever they want.

To make it even easier to unsubscribe from a newsletter, Mailman can add a special footer to each recipient, with a custom URL that allows to unsubscribe without having to remember one’s password.

To enable this feature, you have to enable the following line in /etc/mailman/mm_cfg.py:

# Extra options
# Allow to personalize each message
# (useful to provide a password-less unsubscribe link)
OWNERS_CAN_ENABLE_PERSONALIZATION = 1

Restart Mailman (/etc/init.d/mailman restart) and go to the administrative interface for your list. Under Non digest options, you will then be able to set the Should Mailman personalize each non-digest delivery? option to Full Personalization.

Then, you can set a custom footer for each recipient in the Footer added to mail sent to regular list members option. Here is an example:

_______________________________________________
Bootlin quarterly newsletter
Unsubscribe: %(user_optionsurl)s?password=%(user_password)s
Archives: https://lists.bootlin.com/pipermail/newsletter/

Beware that sending custom e-mails to each recipient will increase the load on your server. You may not want to do this on mailing lists with great numbers of subscribers.

Useful resources

The below ressources were useful to prepare this HOWTO document:

Don’t hesitate to ask questions and give feedback by leaving a reply below.

Bootlin at the Android Builders Summit and the Embedded Linux Conference: one talk and video recording

A good part of the Bootlin team will be in San Francisco (actually, not in San Francisco, but in the Bay Area) from February, 13th to 17th for the Android Builders Summit and the Embedded Linux Conference.

Android Builders Summit 2012
Android Builders Summit 2012

The Android Builders Summit is the second edition of this conference dedicated to Android system development (and not application development). Compared to last year, the conference has been extended to three parallel tracks during two days. There are many talks about Android customization, Android internals, Android porting, usage of Android in specific markets (medical devices, vehicle infotainment), etc. A lot of useful talks for developers working at the Android system level.

Embedded Linux Conference 2012
Embedded Linux Conference 2012

The Embedded Linux Conference is now a well-established conference. Again for this 2012 edition, there will be three parallel tracks during three days. There will be talks about many, many topics: performance and optimization, power management, build systems, drivers for various types of devices, multimedia, ARM kernel support and much more.

I will be giving a talk about Buildroot: A Nice, Simple and Efficient Embedded Linux Build System on the second day of the conference. The aim of the talk is to give a status on where Buildroot is, three years after a maintainer was chosen and a big clean up work was started. The project has changed a lot compared to its state three years ago, so I thought it would be nice to make a status on where Buildroot and where it is going.

With my colleagues Grégory Clément and Maxime Ripard, we will also record all the talks from the Embedded Linux Conference in order to put the videos online, freely available, after the conference, as we have done for many past conferences.

We hope to meet you in San Francisco for the Android Builders Summit and the Embedded Linux Conference!

Bootlin at FOSDEM: two talks and video recording

I'm going to FOSDEMAs usual, Bootlin will again be present at the FOSDEM conference in Brussels, on February, 4th and February 5th. We will of course mostly be attending the Embedded DevRoom, with multiple talks around development in the embedded space.

We will also be giving two talks this year:

  • My colleague Maxime Ripard will be giving a talk about IIO, a new subsystem for I/O devices. In short, IIO is a new subsystem in the kernel to write drivers for devices like Analog-to-Digital converters. Maxime has worked on a driver inside the IIO subsystem for the internal ADCs of the AT91 processors from Atmel, and will base his talk mostly on the experience developing this driver. This talk will take place on Saturday, 12:00 AM to 1:00 PM in the Lameere room.
  • I will be giving a talk on Using Qt for non-graphical applications. It is a talk that has already been given at the Embedded Linux Conference Europe, but the audience of FOSDEM and ELCE being quite different, we have chosen to propose it for FOSDEM as well, and it got accepted. This talk will take place on Sunday, 1:00 PM to 2:00 PM in the Lameere room.

There are also other talks that are worth noting: a SoC power management talk from Jean Pihet who works on OMAP power management support in the Linux kernel, a talk about OpenCores and OpenRISC, a talk about Safe Upgrade of Embedded Systems by Arnout Vandecappelle, who contributes a lot to Buildroot, and also other talks about OpenWRT, Yocto, licensing issues in Android, the EFL libraries, and more.

We will also be carrying our camcorder to video record those talks. We are trying to see with the FOSDEM organization team if it possible to record the audio directly from the room sound systems in order to provide better audio quality in our videos.

If you happen to be at FOSDEM, we’d be very happy to meet you!

Buildroot Developer Day, Brussels edition

BuildrootAround each FOSDEM conference and Embedded Linux Conference Europe event, we have been organizing a Buildroot Developer Day for a few years, in order to gather some developers and users of the Buildroot build system, in order to discuss the development of Buildroot, its features, development process, design, and more.

In Prague at the last Embedded Linux Conference Europe in October 2011, we had a very interesting meeting that gathered developers from other build systems (OE-lite, OpenBricks and PXTdist), and we published a report of this meeting.

The next Buildroot Developer Day will take place on Friday, 3rd February, just before the FOSDEM conference, in Brussels. This is the first meeting that will gather such a number of Buildroot developers: Peter Korsgaard (Buildroot maintainer), Arnout Vandecapelle (developer from Essensium/Mind, who has been contributing a lot to Buildroot lately), Thomas De Schampheleire (also a big contributor in the last year or so), Luca Ceresoli, Yann E. Morin (developer of Crosstool-NG), my colleague Maxime Ripard (who contributed package enhancements and improvements of the package infrastructure) and myself.

This meeting is open to all Buildroot developers and users, and will take place in a location easily accessible in the center of Brussels. Do not hesitate to contact me at thomas.petazzoni@bootlin.com if you want to take part to this meeting.

mkenvimage: a tool to generate a U-Boot environment binary image

Many embedded devices these days use the U-Boot bootloader. This bootloader stores its configuration into an area of the flash called the environment that can be manipulated from within U-Boot using the printenv, setenv and saveenv commands, or from Linux using the fw_printenv and fw_setenv userspace utilities provided with the U-Boot source code.

This environment is typically stored in a specific flash location, defined in the board configuration header in U-Boot. The environment is basically stored as a sequence of null-terminated strings, with a little header containing a checksum at the beginning.

While this environment can easily be manipulated from U-Boot or from Linux using the above mentioned commands, it is sometimes desirable to be able to generate a binary image of an environment that can be directly flashed next to the bootloader, kernel and root filesystem into the device’s flash memory. For example, on AT91 devices, the SAM-BA utility provided by Atmel is capable of completely reflashing an AT91 based system connected through the serial port of the USB device port. Or, in factory, initial flashing of devices typically takes place either through specific CPU monitors, or through a JTAG interface. For all of these cases, having a binary environment image is desirable.

David Wagner, who has been an intern with us at Bootlin from April to September 2011, has written a utility called mkenvimage which just does this: generate a valid binary environment image from a text file describing the key=value pairs of the environment. This utility has been merged into the U-Boot Git repository (see the commit) and will therefore be part of the next U-Boot release.

With mkenvimage you can write a text file uboot-env.txt describing the environment, like:

bootargs=console=ttyS0,115200
bootcmd=tftp 22000000 uImage; bootm
[...]

Then use mkenvimage as follows:

./tools/mkenvimage -s 0x4200 -o uboot-env.bin uboot-env.txt

The -s option allows to specify the size of the image to create. It must match the size of the flash area reserved for the U-Boot environment. Another option worth having in mind is -r, which must be used when there are two copies of the environment stored in the flash thanks to the CONFIG_ENV_ADDR_REDUND and CONFIG_ENV_SIZE_REDUND. Unfortunately, U-Boot has chosen to have a different environment layout in those two cases, so you must tell mkenvimage whether you’re using a redundant environment or a single environment.

This utility has proven to be really useful, as it allows to automatically reflash a device with an environment know to work. It also allows to very easily generate a different environment image per-device, for example to contain the device MAC address and/or the device serial number.

Buildroot 2011.11 released: details on new features

As planned, Buildroot 2011.11 has been released at the end of November. You can download this release as a tarball or through the Git repository.

This release brings a set of new features on which I thought it would be nice to give some details.

The file and local site method

Each package in Buildroot defines from where the source code for the particular component being built is fetched. Buildroot has of course always supported fetching a tarball from HTTP of FTP servers. Later on, Buildroot has added support for fetching from Git, Subversion and Bazaar repositories, for example by doing:

MYPKG_SITE = http://somelocation.com/svn/foobar/trunk
MYPKG_SITE_METHOD = svn

or

MYPKG_SITE = git://somelocation.com/foobar.git

The <pkg>_SITE_METHOD variable allows to define the fetching method. When not specified, Buildroot tries to guess it from the <pkg>_SITE value. Of course, in ambiguous cases such as Subversion or Git repositories over HTTP (as shown in the first example), the <pkg>_SITE_METHOD must be specified.

This new version of Buildroot brings two new site methods: file and local.

The file site method allows to specify the location of a local tarball as the source code for the component to be built. For example:

MYPKG_SITE = /opt/software/something-special-1.0.tar.gz
MYPKG_SITE_METHOD = file

This can be useful for internal software that isn’t publicly available on a HTTP or FTP server or in a revision control system. This new site method was added by David Wagner, who has been an intern at Bootlin between April and September this year.

The new local site method allows to specify the location of the source code to be built as a local directory. Buildroot will automatically copy the contents of this directory into the build directory of the component and build it from here. This is very useful because it allows to version control your source code as you wish, make changes to it, and easily tell Buildroot to rebuild your component. Note that the copy is using rsync so that further copies are very fast (see the pkg-reconfigure and pkg-rebuild targets below). An example of using the local site method:

MYPKG_SITE = /opt/software/something-special/
MYPKG_SITE_METHOD = local

This new site method has been implemented by myself, as the result from my experience of using Buildroot with various Bootlin customers.

The source directory override mechanism

The local site method described above is great for packaging special components that are specific to the embedded device one is working on, like the end-user application, or special internal libraries, etc.

However, there are cases where it is needed to work with a specific version of an open-source component. This is typically the case for the Linux kernel or the chosen bootloader (U-Boot, Barebox) or with other components. In that case, one may want to keep using Buildroot to build those components, but tell Buildroot to fetch the source code from a different location than the official tarball of the component. This is what the source directory override mechanism provide.

For example, if you want Buildroot to use the source code of the Linux kernel from /opt/project/linux/ rather than download it from a Git repository or as a tarball, you can write the following variable definition in a board/company/project/local.mk file:

LINUX_OVERRIDE_SRCDIR = /opt/project/linux

Then, you reference this file through the BR2_PACKAGE_OVERRIDE_FILE option, in Build options -> location of a package override file. When building the Linux kernel, Buildroot will copy the source code from /opt/project/linux into the kernel build directory, output/build/linux-VERSION/ and then start the build process of the kernel.

Basically, this mechanism is exactly like the local site method described previously, except that it is possible to override the source directory of a package without modifying the package .mk file, which is nice for open-source packages supported in Buildroot but that require local modifications.

To summarize, here is my recommendation on how to use Buildroot for packages that require project-specific modifications:

  • You are using an existing open-source component on which you make some tiny bug fixes or modifications. In this case, the easiest solution is to add additional patches to the package directory, in package/<thepackage>/.
  • You are using an existing open-source component, but are making major changes to it, that require proper version control outside of Buildroot. In this case, using the source directory override feature is recommended: it allows to keep the Buildroot package .mk file unmodified while still using your custom source code for the package.
  • You have project-specific libraries or applications and want to integrate them in the build. My commendation is to version control them outside of Buildroot, and then create Buildroot packages for them using the local site method. Note that in the pkg_SITE variable, you can use the $(TOPDIR) variable to reference the top source directory of Buildroot. I for example often use MYAPP_SITE = $(TOPDIR)/../myapplication/.

The <pkg>-rebuild and <pkg>-reconfigure targets

For a long time, when one wanted to completely rebuild a given package from scratch, a possibility was has been to remove its build directory completely before restarting the build process:

rm -rf output/build/mypackage-1.0/
make

Or, using the -dirclean target available for each package:

make avahi-dirclean
make

As these commands remove completely the build directory, the build process is restarted from the beginning: extracting the source code, patching the source code, configuring, compiling, installing.

In 2011.11, we have added two new per-package targets to make it easy to use Buildroot during the development of components:

  • make mypkg-reconfigure will restart the build process of mypkg from the configuration step (the source code is not re-extracted or repatched, so modifications made to the build directory are preserved)
  • make mypkg-rebuild will restart the build process of mypkg from the compilation step (the source code is not re-extracted or repatched, the configuration step is not redone)

So, a typical usage could be:

emacs output/build/mypkg-1.0/src/foobar.c
make foobar-rebuild

However, beware that all build directories are removed when you do make clean, so the above example is only useful for quick testing of changes.

The case where the -reconfigure and -rebuild are really useful is in combination with the local site method or the source override directory mechanism. In this case, when pkg-reconfigure or pkg-rebuild is invoked, a synchronization of the source code is done between the source directory and the build directory is done before restarting the build.

Let’s take the example of a package named mypkg for which package/mypkg/mypkg.mk contains:

MYPKG_SITE = /opt/mypkg
MYPKG_SITE_METHOD = local

Then, to work on your package, you can simply do

emacs /opt/mypkg/foobar.c    # Edit as usual your project
make mypkg-rebuild           # Synchronizes the source code from
                             # /opt/mypkg to the build directory
                             # and restart the build

Integration of real-time extensions

In this 2011.11, an interesting addition is the integration of the Xenomai and RTAI real-time extensions to the Linux kernel. The Xenomai integration was initially proposed by Thomas de Schampheleire and then extended by myself, and I have also added the RTAI integration. This integration allows to seamlessly integrate the kernel patching process and the compilation of the required userspace libraries for those real-time extensions.

Conversion of the documentation to asciidoc

Back in 2004, one of my first contribution to Buildroot was to start writing documentation. At the time, the amount of documentation was small, so a single and simple HTML document was sufficient. Nowadays, Buildroot documentation has been extended significantly, and will have to be extended even further in the future. The approach of a single raw HTML document was no longer up to the task.

Therefore, I have worked on converting the existing documentation over to the asciidoc format. This allows us to split the source of the documentation in several files, for easier edition, and allows to generates a documentation in multiple formats: single HTML, split HTML, raw text or PDF.

Just run make manual in Buildroot 2011.11 to generate the manual. Note that the version available on the website is still the old HTML version, but it should soon be updated to the new asciidoc version.

Bootlin contributions

Bootlin has again contributed to this Buildroot release:

$ git shortlog -sen 2011.08..2011.11 | head -12
   126	Peter Korsgaard
   104	Gustavo Zacarias
    62	Thomas Petazzoni, from Bootlin
    27	Yann E. MORIN
    21	Sven Neumann
    13	Yegor Yefremov
    10	Thomas De Schampheleire
     7	H Hartley Sweeten
     5	Frederic Bassaler
     4	Arnout Vandecappelle (Essensium/Mind)
     4	Maxime Ripard, from Bootlin
     3	Baruch Siach

Our contributions have been:

  • Implementation of the source directory override mechanism
  • Implementation of the local and file site methods
  • Implementation of the pkg-rebuild and pkg-reconfigure targets
  • Conversion of the documentation to asciidoc and documentation improvements
  • Various improvements for external toolchain support: optimization of the toolchain extraction and copy (reduced build time), integration of the support of the CodeSourcery x86 toolchains, update of all CodeSourcery toolchains to the latest available versions
  • Removed useless arguments from the CMAKETARGETS, AUTOTARGETS and GENTARGETS macros, used by all packages in Buildroot. Instead, such pieces of information are automatically figured out from the package .mk file location in the source tree
  • Added the cifs-utils package (for mounting CIFS network filesystems), the libplayer package, the picocom package.
  • Cleanup, improve and merge the Xenomai integration done by Thomas de Schampheleire, and implement the RTAI integration
  • Did a lot of cleanup in the source tree by creating a new support/ directory to contain various tools and scripts needed by Buildroot that were spread over the rest of the tree: the kconfig source code, the special libtool patches, various scripts, etc.

Next release cycle and next Buildroot meeting

The next release cycle has already started. After the meeting in Prague, it was decided that Peter Korsgaard (Buildroot maintainer) would maintain a next branch between the -rc1 and the final version of every release, in order to keep merging the new features for the next release while debugging the current release. This next branch for 2012.02 has already been merged. For example, the addition of the scp and Mercurial site methods has already been merged for 2012.02, as well as numerous other package updates.

On my side, besides usual package updates, I’d like to focus my work for this 2012.02 cycle on improving the testing coverage and on improving the documentation. My colleague Maxime Ripard is working on integrating systemd into Buildroot, as an alternate init mechanism.

The Buildroot community will also be organizing its next meeting in Brussels, on Friday February, 3rd 2012, right before the FOSDEM conference. Buildroot users and developers are invited to join, just contact us through the Buildroot mailing list.

Embedded Linux Conference Europe 2011 videos

One week after the end of the Embedded Linux Conference Europe 2011, we are pleased to release the videos of all talks that took place during this event. We would like to thank the Linux Foundation for allowing us to record those talks and to share freely the resulting videos on-line, and also thank the Clarion Congress Hotel technical staff for helping us with technical details related to video recording.

Below, you’ll find 51 videos, in both a 1920×1080 HD format and a reduced 800×450 format. In total, it represents 28 GB of video, for a duration of 2214 minutes, that is more of 36 hours of video. We hope that you will enjoy those videos and that these will be useful to those who couldn’t attend the conference.

Jim ZemlinVideo capture
Executive Director of The Linux Foundation
Imagine a World Without Linux
Video (24 minutes):
full HD (220M), 450×800 (76M)

Linus Torvalds, Alan Cox, Thomas Gleixner, Paul McKenneyVideo capture
moderated by Lennart Poettering
Kernel Developer Panel
Video (55 minutes):
full HD (622M), 450×800 (191M)

Zach PfefferVideo capture
Linaro
Linaro’s Android Platform
Video (45 minutes):
full HD (604M), 450×800 (164M)

Thomas GleixnerVideo capture
Linutronix
State of PREEMPT_RT
Video (46 minutes):
full HD (374M), 450×800 (147M)

Jessica ZhangVideo capture
Intel
The Yocto Project Eclipse plug-in: An effective IDE environment for both Embedded Application and System developers
Video (45 minutes):
full HD (431M), 450×800 (118M)

Satoru UedaVideo capture
Sony Corporation / Japan OSS Promotion Forum
Contributing to the Community? Does your Manager Support You?
Video (42 minutes):
full HD (556M), 450×800 (140M)

Benjamin ZoresVideo capture
Alcatel-Lucent
Embedded Linux Optimization Techniques: How Not To Be Slow
Slides
Video (44 minutes):
full HD (328M), 450×800 (125M)

Ohad Ben-CohenVideo capture
Texas Instruments
Remote Processor Messaging
Slides
Video (48 minutes):
full HD (433M), 450×800 (131M)

Jeff Osier-MixonVideo capture
Intel
Collaborative Initiatives in Embedded Linux
Video (26 minutes):
full HD (266M), 450×800 (73M)

Karim YaghmourVideo capture
Opersys Inc.
Leveraging Android’s Linux Heritage
Video (51 minutes):
full HD (419M), 450×800 (168M)

Pierre TardyVideo capture
Intel
Using pytimechart For Real World Analysis
Slides
Video (51 minutes):
full HD (495M), 450×800 (132M)

Arnd BergmannVideo capture
Linaro
Optimizations for Cheap Flash Media
Video (44 minutes):
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Saving Power with Wi-Fi: How to Prolong Your Battery Life and Still Stay Connected
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Developing Embedded Linux Devices Using the Yocto Project and What’s new in 1.1
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Kyoto Micro Computer
Android is NOT Just “Java on Linux”
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Bootlin
Using Buildroot For a Real Project
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Sony Network Entertainment
Status of Embedded Linux BoFs
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Instituto Nokia de Tecnologia, Intel
The Linux NFC Subsystem
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Texas Instruments
Board Bringup: LCD and Display Interfaces
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President of Global Solutions at Ixonos
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Chief Linux and Open Source Technologist at Intel
Reflection on 20 Years of Linux
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Ideas on Board
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SOC Power Management – Debugging and Optimization Techniques
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Synopsys
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NEC and Linux Foundation Board Member
Toward the Long Term Stable Kernel tree for The Embedded Industry
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Report from the Buildroot Developer Day

Right after the Embedded Linux Conference Europe, a new edition of the Buildroot Developer Day took place on Saturday, 29th October 2011 in Prague.

Unlike past Buildroot Developer Day that were followed only by Buildroot developers and Yann E. Morin as the crosstool-NG maintainer, this edition of the Buildroot Developer Day was followed by developers of other build systems: Robert Schwebel from PTXdist, Esben Haabendal from OE-lite and we also had the opportunity to discuss with Benjamin Zores and Davide Calvalca from OpenBricks. This made the day very interesting, even though if it was a bit less focused on Buildroot than expected.

I have written and sent a complete report of the discussions, which were about the following topics:

  • Expanding the send-patches.org initiative. This was an important topic, as developers of several build systems had the opportunity to discuss it during this meeting.
  • The testing infrastructure of Buildroot, how to improve it.
  • Package management. A long requested feature for Buildroot, but which would make Buildroot a lot more complicated and probably less reliable. Following this meeting, our position is to not implement such a feature and to keep Buildroot simple. Should package management be necessary, there are other build systems that implement such a feature (at the expense of higher complexity, of course).
  • Toolchain backend. We will soon switch to using the crosstool-NG backend as the default method of building toolchains in Buildroot. Long term, we would like to get rid of the code that builds a toolchain in Buildroot in order to factorize the efforts at the level of the crosstool-NG project.
  • Migration of the documentation to the asciidoc format has been accepted, and the next version of Buildroot will feature this updated documentation.
  • Out-of-tree build of packages. This is a very internal question to how Buildroot builds package. See the report for details.
  • Website improvement, because the current Buildroot website is quite ugly.
  • Maintenance process. We are seeing a quite significant increase in the number of contributions to Buildroot and some of these contributions are taking more and more time to get integrated. We discussed the topic and came up with a few proposals on how to improve the situation.
  • Host packages visible in menuconfig. Traditionally, packages built for the host are not user-selectable as Buildroot since they are just dependencies to build target packages. However, we had the case of some host packages that should be user-selectable. The principle has been agreed upon.
  • Per-package device file handling. A mechanism proposed by Maxime Ripard, from Bootlin, to allow each package to specify special permissions/owernships/device files to install in the target filesystem.
  • Relocatable toolchain and SDK. Buildroot produces a SDK (set of utilities and libraries to build applications for the target independently from Buildroot), but this SDK is currently not relocatable. We discussed the various issues to fix to make it relocatable.
  • Licensing report generation, which is also a feature that has been requested in the past.

All in all, it was a very interesting and motivating day, that got closed by a short visit of Prague’s center and a nice dinner. The next edition of the Buildroot Developer day will take place on Friday, 3rd 2012 in Brussels, the day before the FOSDEM conference. It is open to all Buildroot users and developers!

Regarding Buildroot itself, the maintainer Peter Korsgaard will release 2011.11-rc1 early next week, and 2011.11 by the end of November. This release will have several new useful features, which we will cover in details in a future blog post.

Bootlin at Embedded Linux Conference Europe 2011

The next Embedded Linux Conference Europe will take place from October 26th to October 28th in Prague, together with the first edition of LinuxCon Europe and just after the Kernel Summit, the GStreamer conference and the Real-time Linux workshop: it’s a really impressive concentration of interesting talks for embedded Linux developers. Linus Torvalds is already announced as a keynote speaker of the LinuxCon Europe.

ELCE 2011

As ELCE is a conference that embedded Linux developers simply can’t miss, the complete team of Bootlin will be there: my colleague and Bootlin founder Michael Opdenacker (Michael is part of the organization committee for this event), my engineer colleagues Grégory Clément and Maxime Ripard and myself, Thomas Petazzoni.

I will also have the chance to give two talks during this edition of ELCE:

  • Using Buildroot for real products. As Bootlin has used and is using Buildroot for multiple customer projects, this talk will share our experience on how to configure and setup Buildroot properly to build embedded Linux systems and include in a clean and nice way all of the specificities of each product.
  • Using Qt for non-graphical applications. Qt is often seen only as a graphical library, but it is in fact much more than that. Based on the experience of a customer project, this presentation will detail all the nice features that Qt offers to build embedded applications.

We highly recommend this conference to European embedded Linux developers and hope to meet some of our readers there! We will be the guys behind the video cameras in the embedded rooms. It’s worth mentioning that ELCE attendees are also granted, for free, the right to access LinuxCon Europe talks.

Buildroot 2011.08 released!

Buildroot logoAs promised by the time-based release schedule, a new version 2011.08 of Buildroot has just been released. For those just coming in, Buildroot is a utility that automates the process of building an embedded Linux system: generating a cross-compilation toolchain or importing an existing one, cross-compiling multiple user-space libraries or applications, generating a root filesystem image and building the kernel or bootloader images. We use it extensively at Bootlin for various projects and therefore contribute regularly to this project.

The major highlights of this version are :

  • An updated version of udev. For a long time, Buildroot has been stuck with an ancient udev release, due to the slightly more complicated dependencies of newer udev versions. Fortunately, Yegor Yefremov and other contributors have done the work to integrate those dependencies and get a modern version of udev to work in Buildroot.
  • An updated version of util-linux has been integrated. Here as well, updating it wasn’t completely straightforward, due to utility libraries such as libuuid, which is also present and e2fsprogfs, and used by multiple other packages.
  • The conversion of the Linux kernel build process and the bootloaders build process to the GENTARGETS infrastructure of Buildroot. This makes the build process of the kernel and the bootloaders much more similar to regular packages, and allows to provide the capability of fetching kernel sources not only from tarballs over http/ftp, but also from Git or Subversion repositories.
  • The kernel build process has been extended to support Linux 3.x versions and also release candidates versions.
  • Some improvements for using Buildroot to generate systems for non-MMU targets
  • Some new packages have been added: acl, attr, ebtables, gnutls, inotify-tools, ipset, libargtable2, libiqrf, libmnl, libnspr, libnss, libroxml, libyaml, live555, mxml, orc, rsyslog, sredird, statserial, stunnel, ti-utils, uboot-tools, yajl, and many, many packages have been upgraded or fixed.

The amount of patches merged for this release (287) is almost identical to the number of patches for the past release (286), but the number of contributors has increased from 28 to 35. Generally speaking, we are seeing an increasing number of requests and contributions from users :

   143  Peter Korsgaard
    36  Thomas Petazzoni
    21  Sven Neumann
    13  Gustavo Zacarias
    13  Yegor Yefremov
     9  Maxime Ripard
     7  Yann E. MORIN
     4  Baruch Siach
     4  Daniel Mack
     4  Luca Ceresoli
     3  Jean-Christophe PLAGNIOL-VILLARD
     3  Thomas De Schampheleire
     2  Allan W. Nielsen
     2  Mike Williams
     2  Phil Edworthy
     2  Will Newton
     1  Arnout Vandecappelle (Essensium - Mind)
     1  Arnout Vandecappelle (Essensium/Mind)
     1  Benoit Mauduit
     1  Benoît Mauduit
     1  Daniel Hobi
     1  Daniel Nyström
     1  Danomi Mocelopolis
     1  Evgeni Dobrev
     1  Francis Mendes
     1  Frederic Bassaler
     1  Frederik Pasch
     1  H Hartley Sweeten
     1  Heiko Helmle
     1  Marek Belisko
     1  Michael J. Hammel
     1  Milton Soares Filho
     1  Philippe Reynes
     1  Robin Holt
     1  Tristan Lelong

Two developers from Bootlin have contributed patches for this release: my colleague Maxime Ripard has contributed 9 patches (Python build fixes, toolchain configuration fix, new rsyslog package, rework of the logging init scripts, new stunnel package, /dev/shm fix for the initialization scripts, code cleanup) and I (Thomas Petazzoni) have contributed 36 patches (conversion of the kernel and bootloaders to the GENTARGETS infrastructure, support for Linux 3.x and release candidates, improvements for non-MMU targets, the new scons package, upgrade of valgrind, some other code cleanup and fixes).

For the next release, I expect to contribute a set of patches that has already been reviewed on the list, and which adds the possibility of building packages from an existing source directory instead of letting Buildroot handle the download/extract/patch part of the build process. This feature will make it much much easier to use Buildroot during the development of the kernel, an application or a library for the target embedded system. I have also posted patches that convert the documentation over to the asciidoc format and I intend to do various additions to this documentation.

It is also worth mentioning that the Buildroot developers (Peter Korsgaard and myself) and the Crosstool-NG maintainer Yann E. Morin are organizing a Developer Day on October, 29th in Prague, the day after the Embedded Linux Conference Europe. All developers or users interested in Buildroot and/or Crosstool-NG are invited to join. See http://lists.busybox.net/pipermail/buildroot/2011-August/045066.html for more details.