Kernel Recipes 2016 - The Free Software Bastard Guide

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Developer, Enterprise, there are many ways to be a Free Software bastard. This talk will give you some useful hints to become the best asshole in communities. Clément Oudot – Clément Oudot works for Savoir-faire Linux, a worldwide FOSS company. He is the leader of LemonLDAP::NG, a free WebSSO and Access Management software. He also works for other LDAP-related projects (OpenLDAP, LDAP Tool Box, LDAP Synchronization Connector).

@CreativeConnard
the Free Software
Bastard Guide
Disclaimer: explicit content, do not reproduce in real life

~ 2 ~@CreativeConnard
HOW TO
be an asshole
~ User ~
~ Developer ~
~ Company ~

~ 4 ~@CreativeConnard
Chapter #1
[ Mailing lists ]

~ 5 ~@CreativeConnard
Don’t use lists
Send mail directly to project leaders※
Paste stack traces on IRC channels※
Use Twitter and Facebook to ask question or report
problems※
※ Open issues in bug tracker to ask questions

~ 6 ~@CreativeConnard
Use the lists
Never register! Let administrators take time to moderate
your message.
Be rude if you don’t get any answer.
※
Use a Vacation Away message to inform all people that
your are not available※
Do not answer to the list but directly to sender. You want
to get help, not to give it.※

~ 7 ~@CreativeConnard
Invite the list to all professional networks

~ 8 ~@CreativeConnard
Write on lists
※
Use your mother thong. Anybody can use a translation tool
to read you.
Answer on top, don’t include original text, use HTML,
include pictures in your signature, TRY TO
UPPERCASE ALL WORDS, put !!! and ??? everywhere
※
※ FEED THE TROLL

~ 9 ~@CreativeConnard
Chapter #2
[ Bugs ]

~ 10 ~@CreativeConnard
Find bugs
※ Use prehistoric version (>2 years old)
※ Use non official patch
※ Use weird operating systems
※ Let your children use the software

~ 11 ~@CreativeConnard
Report bugs
※
Don’t search if the bug was already reported, try to create
duplicates
※ Description “Does not work” is often enough
※
Demand a quick solution for free. Use the word “ASAP”.
Never test the patch because it’s too hard

~ 13 ~@CreativeConnard
Chapter #3
[ Documentation ]

~ 14 ~@CreativeConnard
Acronyms
※ RTFM (Read The Fucking Manual)
※ WITFM (Where Is The Fucking Manual)
※ TODO (Too Old DOcument)
※ RTS (Read The Source)

~ 15 ~@CreativeConnard
Documentation everywhere
※
Create files in project (README, INSTALL) but never
update them
※ Install an open wiki (without authentication)
※
Explain a lot of things on mailing list but never put them in
a documentation

~ 16 ~@CreativeConnard
Chapter #4
[ Quality ]

~ 17 ~@CreativeConnard
TESTING
IS
DOUBTING

~ 19 ~@CreativeConnard
Using Free Software
※ License? Let this to Bob from accounting department
※ OMG they give it for free! Idiots ;)
※ Give something back? We will that next year
※ Community? Are we doing politics here?

~ 20 ~@CreativeConnard
Making Free Software
※ Fork instead of contributing (Fork as a Service)
※
Keep interesting features for “enterprise” edition, because
only big companies use them
※
Create a new license and pay a team of lawyer for this,
because no existing license fits your needs
※
Don’t let external people contribute, they will mess up all
with their dirty hands

~ 21 ~@CreativeConnard
@CreativeConnard
Links for bastards
@DonJon_Legacy
http://donjonlegacy.com/

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Kernel Recipes 2019 - ftrace: Where modifying a running kernel all started

Anne Nicolas

Ftrace’s most powerful feature is the function tracer (and function graph tracer which is built from it). But to have this enabled on production systems, it had to have its overhead be negligible when disabled. As the function tracer uses gcc’s profiling mechanism, which adds a call to “mcount” (or more recently fentry, don’t worry if you don’t know what this is, it will all be explained) at the start of almost all functions, it had to do something about the overhead that causes. The solution was to turn those calls into “nops” (an instruction that the CPU simply ignores). But this was no easy feat. It took a lot to come up with a solution (and also turning a few network cards into bricks). This talk will explain the history of how ftrace came about implementing the function tracer, and brought with it the possibility of static branches and soon static calls! Steven Rostedt

Kernel Recipes 2019 - Suricata and XDP

Anne Nicolas

Suricata is a network threat detection engine using network packets capture to reconstruct the traffic till the application layer and find threats on the network using rules that define behavior to detect. This task is really CPU intensive and discarding non interesting traffic is a solution to enable a scaling of Suricata to 40gbps and other. This talk will present the latest evolution of Suricata that knows uses eBPF and XDP to bypass traffic. Suricata 5.0 is supporting the hardware XDP to provide ypass with network card such as Netronome. It also takes advantage of pinned maps to get persistance of the bypassed flows. This talk will cover the different usage of XDP and eBPF in Suricata and shows how it impact performance and usability. If development time permit, the talk will also cover AF_XDP and the impact on this new capture method on Suricata. Eric Leblond

Kernel Recipes 2019 - Marvels of Memory Auto-configuration (SPD)

Anne Nicolas

System memory configuration is a transparent operation nowadays, something that we all came to expect to just work out of the box. Still, it does happen behind the scenes every single time we boot our computers. This requires the cooperation of hardware components on the mainboard and on memory modules themselves, as well as firmware code to drive these. While it is possible to just let it happen, having a deeper understanding of how it works makes it possible to access valuable information from the operating system at run-time. I will take you through the history of system memory configuration from the mid 70s to now. We will explore the different types of memory modules, how their configuration data is stored and how the firmware can access them. We will see which problems had to be solved along the way and how they were solved. Lastly we will see how Linux supports reading the memory configuration information and what you can do with that information. Jean Delvare

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