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Have a look at the Kernel Janitors Project and perhaps KernelNewbies.org .

...www.kernelnewbies.org is supposed to have a lot for the aspiring kernel hacker.

Those of you anxious to contribute by testing I suggest you get acquainted with the following sites:
Linux Kernel Mailing List FAQ (a must read before submitting bugs or oopses)
Good site about kernel hacking (not just for newbies either)

When I first started getting interested in the kernel I subscribed to the mailing list and was immediately overwhelmed by the traffic. I soon found Kernel Traffic and unsubscribed from the mailing list and was happy.

The truth is, though, that while KT gives a good overview of some areas of the mailing list, it misses a lot. This is obvious, of course; cutting 100's of posts a day down to one moderate weekly summary is going to leave a lot of information. But to be honest, though I admire and appreciate Zach Brown's efforts, I wonder what criteria he uses for deciding what threads to cover. I sometimes feel he has left out some fairly important/interesting stuff while quoting huge gobs of somewhat trivial (imho) threads.

Anyone who is seriously interested in the kernel internals shouldn't really be relying on KT too much. Head over to kernelnewbies and start reading the real list. I recommend a good filternig system to help you separate out the chaff, though.

dan.

Moshe Bar seems to indicate that Alan Cox is creating some kind of fork of the Linux kernel. Actually, -ac kernels are alwasys different from Linux kernels to some extent, since they include slightly more experimental code (e.g. ext3), or code that Linus has not had a chance to review yet. This way, the experimental code gets more testing before going into official Linus kernels. You can read more about -ac kernels at KernelNewbies.Org.

As anyone following LKML knows, Alan thinks that drastic VM changes should be reserved for 2.5, and so continues to keep Rik's VM going. This actually helps quite a bit as both VMs get tested and there have been several comparative tests conducted leading to improvements in both VMs. Competition in this case is certainly helping Linux.

Oh and for all you fork conspirators, here's another fact: Andrea Arcangeli also releases his own kernel releases, called -aa. I don't think any of these are considered forks; everyone understands that this way pacthes get more testing, "crosstalk" between the different flavors is a given.

Much ado about nothing, IMHO...

-Rahul

If you are new to installing your own kernel, or you want to get started on kernel programming, see http://www.kernelnewbies.org/ and join them on IRC in #kernelnewbies on the Open Projects Network.

Also helpful to newbies, or to convince you it's worthwhile to help with testing, is my other article Why We Should All Test the New Linux Kernel.

And finally there is the Kernel HOWTO.

If you'd like to program or debug the kernel, I recommend a couple of books:

• Kernel Projects for Linux by Gary Nutt, ISBN 0-201-61243-7 - this is a lab manual with hands-on kernel programming projects that address a variety of kernel components
• Understanding the Linux Kernel by Bovet, Cassetti, and Oram, ISBN 0596000022 - I bought a number of kernel programming books, and this seemed to be the best written of the books that covered recent kernels. It's mainly 2.2, with short addenda in each chapter for the changes that were expected at the time of writing for 2.4

The Alan Cox series (latest is 2.4.10-ac11) works fine here. I'm currently running 2.4.9-ac18 from a week ago. Here's how to get it. I use gcc 2.95.4 under Debian - as far as I know it was not yet recommended to compile the kernel with 3.0+, but it might work.

Just like the majority of you readers, I am not a kernel developer. But I like to know what I'm running. My conclusion is that if you want a stable kernel, ignore Linus' tree and use the Alan Cox tree. To say it blunt, 2.4.10+ really is 2.5, and you should only run it if you are prepared for some weird behaviour.
Now am I a troll? Hope not. I did get my info out of Kernel Traffic, which I've been reading for months. It is a very good, understandable and clear compression of all important things that happen on the linux kernel mailinglist. If you use Slashdot as your only information portal about the kernel, you are *braindead*.
Ok, now my point - it is the VM subsystem. By now you should know that 2.4.x, until recently 2.4.10, used the VM code by Rik van Riel. That code has taken some time to develop, but you definitely can't blame Rik as the cause for all 2.4 stability problems, as well as the eternal delay of 2.5. But according to the l-k list, Linus himself made several errors in including Rik's patches, which indeed caused 2.4.7 and up to be unstable! Ok, now stop and think about this. Linus has an enormous responsibility. He didn't realize where the fault was, but he did perceive that the stable kernels were NOT stable. He knew that Andrea Arcangeli was still working on his own VM (that work improved Rik's VM too in 2.3. Not having a monopoly really does improve invention!) Then Linus made the big step: even in a *stable* series, he took over Andrea's VM and threw out Rik's one. This is really an important decision, and I applaud it!
The only thing Linus should not have done, is labeling this thing 2.4.10. It really is 2.5. For the big public, that kernel was definitely everything but a stable kernel. Luckily a lot of problems have been solved since (2.4.11 is a hell of a lot better than 2.4.10), and I consider Andrea Arcangeli really a good coder, but actually I trust Alan Cox most. He commented that Linus' recent kernels trashed several boxes of his overnight. Alan really sees the -ac tree as the stable one currently. I run 2.4.9-ac18 too, with the kernel preemption patch as mentioned earlier, on a p2-233 with quite some load, and it doesn't show any strange behaviour. (The kernel preemption patch doesn't do really much here: I still get skips when I record an mp3 from my soundcard and switch desktops in the meantime. But I should not expect wonders :))
One last thing: Rik van Riel's VM has improved *too*. Alan Cox catches up with his patches very speedily. No more big bugs; Rik even added some optimizations in 2.4.9-ac16. I can't see that of course, but overall the system is a lot more responsive than 2.4.3-pre6, my last kernel before this one.
So my advice: use the ac-series of the kernel. Linus has made some wise decisions. I think he should start 2.5 and leave 2.4 to Alan, before people go sulking about 2.4.10 versus the always-stable reputation of the Linux kernel.

Yes this would be much better in the original article.

Turns out the author got sidetracked, but is about to continue work on it.

The homepage is here.

http://www.kernelnewbies.org/~phillips/

• Have you tried a named pipe? Admitted, you can't get ioctls, but for most stuff it's enough. I admit, this would be nice, but I don't think it's high prio.
• Agreed, iirc it's being worked on.
• Being worked on too, again iirc.
• Why? Unless you want to put the whole video-card driver from X/berlin/whatever into the kernel, I really don't see the benefit.
• Being worked on (or at least discussed)
• Been done. There's a patch for 2.0, it's been ported to 2.2 I think. Some day someone'll port it to 2.4 (It could be you... :-)
• Been discussed a lot, linus doesn't like any sacrifices for this...
• Yup
• Yup
• Ehmm, capabilities, ACLs, etc. I think as you've just stated, it already exists.