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David Herrmann
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David Herrmann

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The election process for the X.Org Board of Directors 2016 is open!

On this year's round, you will be asked to elect the next directors which will serve you for the next 4 years. You will also be asked your opinion about moving under the SPI umbrella!

As +Keith Packard put it, your vote is really important! Not voting is sort of equivalent to saying no to the merge, as we need 2/3 of the members to say yes before we can do anything.
X.org Election Time — Vote Now. It's more important than usual to actually get your vote in — we're asking the membership to vote on changes the the X.org bylaws that are necessary for X.org to become a SPI affiliate project, instead of continuing on as a separate organization.
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David Herrmann

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Stop coding, close your editor, and get ready for some history knowledge. Regardless your attitude towards systemd, it's a very pleasant conversation between Tim and Lennart with lots of background information of modern desktop linux. Sadly, German only.

(..and while you're at it, continue browsing on cre.fm, definitely worth your time!)
 
I had the pleasure to participate in one episode of the CRE Podcast (German). Enjoy.
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systemd leitet die neue Generation der Linux Systemarchitektur ein Der einst von Linus Torvalds geschaffene Betriebssystemkernel Linux ist eine freie Reimplementierung der UNIX Betriebssystemfamilie und hat sich in den letzten 20 Jahren sehr eigenständig entwickelt. Der Rest des Systems, das Userland, hat sich aber noch sehr stark an der klassischen Struktur von UNIX orientiert. Mit der Initiative systemd hat sich dies geändert und es entsteht ei...
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Lennart Poettering's profile photoIvan Shapovalov's profile photoParecida Morais's profile photoChristopher Dancy's profile photo
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Sorry to hijack this post but what is this 'bus1' project David and Kay appear to be working on? New bus implementation, staritng from the ground up, to replace kdbus? 
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David Herrmann

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Fun with ISO-C: The kernel commonly checks syscall flags for invalid bits and rejects them. Unfortunately, given the snippet below, `func(1ULL << 50);` will not yield EINVAL. Lovely!

(hint: FLAG_BAR is the culprit)

enum {
        FLAG_FOO = (1ULL << 30),
        FLAG_BAR = (1ULL << 31),
};

int func(uint64_t flags) {
        if (flags & ~(FLAG_FOO | FLAG_BAR))
                return -EINVAL;
        return 0;
}
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David Herrmann's profile photoRay Strode's profile photoCamille Bordignon's profile photoMarcin Ślusarz's profile photo
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+Camille Bordignon In this case both values become ints and everything works thanks to sign extension.
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David Herrmann

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If you invent something new, one of the hardest parts is to convey your concept. In the case of kdbus, I meet a lot of people who don't have a clue what it actually does. On the other hand, most people seem to be pretty familiar with AF_UNIX. Hence, I went ahead and tried to describe the very fundamental concept of kdbus, by "speaking" AF_UNIX.

I hope this makes people re-evaluate their position, if they read some premature judgement about kdbus on news media or forums. I don't believe kdbus is something radically new, nor is it a huge code-base. I much rather believe we just picked the parts of existing features we needed, and formed a fresh new interface that should serve DBus' needs for the years to come.
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Bhaskar Chowdhury's profile photoBart Massey's profile photo
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From what I understand of kdbus, naming it something with dbus in it was actually a mistake. The DBus design and implementation carries a lot of baggage that is irrelevant to the new subsystem. Maybe just kbus would have been better; maybe something like mpxio [reminiscent chuckle]. Anyhow, too late now I guess.
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That feeling when you audit your own code and you're really not sure whether you wanna look behind that tree.
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memfd is merged, thanks to all involved! But lets not get nostalgic, but continue straight to the next task: revoke()
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Lennart Poettering's profile photoBastien Nocera's profile photoRoland Dreier's profile photo
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I think for device drivers at least, this revoke stuff needs a better way to handle mmap, in particular mmap of MMIO space.
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David Herrmann

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"Every step of the way is misery to get the code merged, and I would give up a lot to never work on the Linux kernel again." -- Eric Anholt (open-source RaspberryPi DRM driver)

Again an again, established open-source developers struggle with LKML. I seriously wonder whether we lost our privilege to criticize vendors that refuse to deal with upstream?
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Christopher Dancy's profile photoDave Airlie's profile photoHenrique Almeida's profile photoSriram Ramkrishna (sri)'s profile photo
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Yeah, I got the feeling it was the firmware people that was involved in the bike shedding.
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Another day, another rant on LKML, and again lots of non-kernel-developers defending 'rough style'. sigh, but if you dig deep enough into the comment-sections, you can still find some common sense in there:

"Try reacting this way in the other fields than coding. When you don't like the food or beer in the restaurant, tell them it's sh*t and utter cr*p. Then reason that you didn't insult the people and they just don't get the difference. Do this to your friends when they make mistakes. Surely, you're ranting about the mistakes not about the people. Then enjoy the companion of those who got the difference." +Lubomir Rintel
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Bhaskar Chowdhury's profile photoBryan Jon Smith's profile photoMartin Kühne's profile photo
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And the coders should be grateful that when they don't have developed a sense of quality on their own they get one beaten into them this way.
I'm fine with that.
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We haven't talked much about kdbus recently, but that doesn't mean we weren't busy. The kernel module has matured and provides ABI stability now, we've spent many long evenings on improving the user-space compatibility layer to dbus1, and we've reached out to start converting the other bus-libraries.
My system has been running kdbus just fine for over half a year now. There are, occasionally, some hiccups we have to fix, but the overall experience is pretty neat.

Anyway, why am I writing this: If you run on Fedora Rawhide, you can now test kdbus by simply adding `kdbus=1` to your kernel command-line (or `kdbus=0` to disable it; which is still the default). If you run other distros, we have created a page that describes the required steps shortly [1].

If you have some spare time, we'd greatly appreciate if developers would give this a try. It works fine for us, but there are thousands of other dbus applications in the wild which might not work with the compat layer. Any feedback is highly appreciated! And, if you attend the upcoming systemd conference [2], I'd gladly return the favor with some beer! :)

[1] http://www.freedesktop.org/wiki/Software/systemd/kdbus/
[2] https://systemd.events/
david@david-t2 ~/dev/kdbus $ busctl monitor Monitoring bus message stream. ‣ Type=signal Endian=l Flags=1 Version=2 Priority=0 Cookie=-1 Sender=org.freedesktop.DBus Path=/org/freedesktop/DBus Interface=org.freedesktop.DBus Member=NameOwnerChanged Monotonic=21122678158 Realtime=1438248540378044 ...
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Sriram Ramkrishna (sri)'s profile photoDavid Herrmann's profile photoCristian Rodriguez's profile photoAhmed S. Darwish's profile photo
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+Cristian Rodriguez Hmm, there's something strange in my setup then and I thought "--disable-systemd" was the reason.

I have kdbus=1 in the kernel parameters, but `busctl monitor' still shows empty DESCRIPTION columns and /sys/fs/kdbus exists but does not have a 0-system entry. Not sure if this means a working kdbus setup or not; need to read further in the documentation.
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So for quite some time, if I switch from X11 to fbcon, I get a graphical animation that "moves" the fbcon content into the screen from the right / left border depending where I switch to. The animation is a bit clumsy and if you look closely, you notice it takes exactly 4 frames, and each frame moves the content by exactly 25% to the left / right. It never bothered me that it wasn't really smooth (I mean, it's the same people that wrote motif, right?), I just imagined some gfx-developer looking at the result and being satisfied. Which in turn made me happy.

That changed radically today, after I tried asking the DRI developers where that code is implemented. Turns out, no-one was aware of that animation and it's very likely a bug in the SNA code of the intel DDX.

Long story short: I wish I could screw up in my code and it would produce a fancy feature. All I get is angry users.. sigh
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Rob Clark's profile photoAlex B's profile photo
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Alex B
 
I once faced a similar bug in racing game for J2EE. Tester said that if he press 2,8 and 9, car will jump. Funny thing that Y coor of car was fixed and never changed. Appears that device was too slow to process user input and draw new piece of the road. And without proper synchronization it caused visual effect of jumping car.
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"I � Unicode."
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Ismael Castiñeira Álvarez's profile photoDaniel Mack's profile photo
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Die Unicode Selbsthilfegruppe trifft sich heute im Gr¶nen Saal
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Please help us defend our trademark from Groupon and support GNOME!  

"GNOME" the trademark has been a familiar name for the past 17 years in the Free and Open Source Software community. The GNOME project has been a staple desktop for GNU/Linux and BSD desktops. It was the default desktop for Sun Microsystems workstation class machines, continues to be the default desktop for the Red Hat Enterprise Linux and SUSE Linux Enterprise Server distributions, and it is the default desktop of Fedora and Debian. SUSE Linux Enterprise Point of Service solution for the retail industry is based on GNOME. GNOME technology can be found in TVs, tablets, phones, consumer devices, and in common software everywhere.

Recently Groupon announced a product with the same product name as GNOME. Groupon’s product is a tablet based point of sale “operating system for merchants to run their entire operation." The GNOME community was shocked that Groupon would use our mark for a product so closely related to the GNOME desktop and technology. It was almost inconceivable to us that Groupon, with over $2.5 billion in annual revenue, a full legal team and a huge engineering staff would not have heard of the GNOME project, found our trademark registration using a casual search, or even found our website, but we nevertheless got in touch with them and asked them to pick another name. Not only did Groupon refuse, but it has now filed even more trademark applications (the full list of applications they filed is available on our groupon page linked). To use the GNOME name for a proprietary software product that is antithetical to the fundamental ideas of the GNOME community, the free software community and the GNU project is outrageous. Please help us fight this huge company as they try to trade on our goodwill and hard earned reputation.

We want to show that our brand matters and that you care. Of the 28 trademark applications Groupon filed, we have to file formal proceedings to oppose 10 of them by December 3, 2014. Help us raise the funds to fight back and most of all call public attention to this terrible behavior by Groupon. Help us make sure that when people hear about GNOME software they learn about freedom and not proprietary software. Our counsel has advised us that we will need $80,000 to oppose the registration of the first set of 10 applications. If we are able to defend the mark without spending this amount, we will use the remaining funds to bolster and improve GNOME. Please help us raise the money to protect GNOME's trademark and strengthen Free Software!

Please donate here:
http://www.gnome.org/groupon/
"GNOME" the trademark has been a familiar name for the past 17 years in the Free and Open Source Software community. The GNOME project has been a staple desktop for GNU/Linux and BSD desktops. It was the default desktop for Sun Microsystems workstation class machines, continues to be the default ...
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