Kernel Traffic #290 For 3 Jan 2005

By Zack Brown

Table Of Contents

Mailing List Stats For This Week

We looked at 1325 posts in 8550K.

There were 386 different contributors. 198 posted more than once. 170 posted last week too.

The top posters of the week were:

1. Copyright Assignments For ReiserFS And XFS

11 Nov 2004 - 18 Nov 2004 (72 posts) Subject: "2.6.10-rc1-mm5"

Topics: FS: ReiserFS, FS: XFS, Kernel Release Announcement

People: Adrian BunkLinus TorvaldsChristoph HellwigHans ReiserAndrew Morton

Andrew Morton announced Linux 2.6.10-rc1-mm5, with no spectacular changes, and Adrian Bunk noticed the following copyright statement in the Reiser 3 and 4 code:

Reiser4 is hereby licensed under the GNU General Public License version 2.

Source code files that contain the phrase "licensing governed by reiser4/README" are "governed files" throughout this file. Governed files are licensed under the GPL. The portions of them owned by Hans Reiser, or authorized to be licensed by him, have been in the past, and likely will be in the future, licensed to other parties under other licenses. If you add your code to governed files, and don't want it to be owned by Hans Reiser, put your copyright label on that code so the poor blight and his customers can keep things straight. All portions of governed files not labeled otherwise are owned by Hans Reiser, and by adding your code to it, widely distributing it to others or sending us a patch, and leaving the sentence in stating that licensing is governed by the statement in this file, you accept this.

Adrian said:

I have no problem with dual-licensed code, but I do strongly dislike having this "unlike you explicitley state otherwise, you transfer all rights to Hans Reiser" in the kernel.

Besides the fact that giving the copyright completely away is nothing that is legally possible in at least Germany, I'm not happy with having to check every single file in the source tree for additional licence clauses before editing it - and then to consider whether my contribution might deserve a copyright label according to my local law.

Linus Torvalds replied:

I don't see any reasonable alternatives. The alternative is for Hans Reiser to not be able to merge with the kernel, which is kind of against the _point_ of having a dual license.

If the wording grates or assignment is an issue (and yes, in the US you technically really need to have an express _signed_ assignment, implied assignments just don't work), asking people to make their changes PD instead might work (they'd obviously immediately be subsumed under the GPL as far as the kernel is concerned, but would allow the dual-licensing to continue to work).

That said, I don't think at least _this_ particular area has been problematic, because quite frankly, very few people end up working on other peoples filesystems, so as far as I can tell, almost all reiserfs fixes have really been mainlt due to interface changes, nothing else. So assignment of copyright etc doesn't really ever become an issue, if only because copyrights require a bit of actual artistic value ;)

Christoph Hellwig pointed out:

If you touch e.g. XFS for a non-trivial change you'll also get a mail from SGI politely asking to assign your copyright. Doing this implicit is IMHO a reall bad thing.

IF you really think it's something we should do the least thing to do is to put a BIG WAIVER into every file for which this is in effect.

He added that a few years ago, Hans Reiser took the same route as SGI, instead of the current implicit assignment. At one point down the thread, Hans replied:

Please understand it as the emphasis is on don't obscure and distort my definition in my labeling of the code of what I have copyrights to. I believe that for that reason, a court would allow it. I could be wrong. That is why I ask everyone I detect for a copyright assignment, still to this day. I don't 100% trust the code acceptance process to guarantee that I will catch everyone....

In a world with SCOs, we need to be over careful not under careful about such things.

2. Linux 2.6.10-rc2-mm4 Released

30 Nov 2004 - 14 Dec 2004 (53 posts) Subject: "2.6.10-rc2-mm4"

Topics: Kernel Release Announcement, Virtual Memory

People: Andrew MortonAndrew Morton

Andrew Morton announced Linux 2.6.10-rc2-mm4, saying:

http://www.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.10-rc2/2.6.10-rc2-mm4/

3. Status Of IBM HD Shock Detection

1 Dec 2004 - 13 Dec 2004 (22 posts) Subject: "[WISHLIST] IBM HD Shock Detection in Linux"

People: Robert LoveIan SoboroffLee RevellAlan CoxShawn Starr

Shawn Starr asked if anyone was working on IBM's HD shock detection; Lee Revell had never heard of this, and Robert Love explained:

Modern ThinkPads have accelerometers in their hard drives that detect sudden movement and spin down the drive or otherwise protect it.

The device is pretty basic, though, and you can just read it directly to watch the movement of your laptop. E.g., pick your laptop up and a little icon in your GNOME panel can show an up arrow. Pretty neat.

I am sure Google has more information.

Ian Soboroff added:

This needs to be added to the input layer!

Till Harbaum wired up an accelerometer inside his Palm Pilot, then wrote a marble rolling game that you could play by tilting the palm to move the marble. http://www.harbaum.org/till/palm/adxl202/index.html

Kay Sievers gave a link to an IBM whitepaper (ftp://ftp.software.ibm.com/pc/pccbbs/mobiles_pdf/aps2mst.pdf) on shock detection. Shawn asked for more technical details, and Lee kvetched, "Exactly. All the IBM people on this list and not one remotely useful post. I can contact marketing@ibm.com or something if I want a bunch of fluff. That whitepaper is just a user level guide for the Windows driver ferchrissake. Obviously it's a motion detector on the motherboard. How do we freaking TALK to it? As in, what bits to we write to what registers to do what." Kay suggested reverse-engineering the Windows driver, but Lee retched into his hand, and suggested that Shawn ask IBM for the data-sheet. Alan Cox remarked at this point, "IBM are still really really bad about external data sheets and the like. I spent over three years chasing IBM for docking station chip information."

4. Disk ioctl Documentation

9 Dec 2004 - 13 Dec 2004 (2 posts) Subject: "[PATCH] final polish on disk ioctl documentation"

Topics: Disks: IDE, Ioctls

People: Edward FalkBartlomiej Zolnierkiewicz

Edward Falk, continuing the work covered in Issue #287, Section #15  (18 Nov 2004: Documenting ioctls) and Issue #288, Section #3  (23 Nov 2004: IDE And CDROM ioctl Documentation) , posted a patch to polish off disk ioctl documentation; and Bartlomiej Zolnierkiewicz applied it.

5. SquashFS Likely To Go Into Official Tree

10 Dec 2004 - 13 Dec 2004 (8 posts) Subject: "[Announce] Squashfs 2.1 released (compressed filesystem)"

Topics: Access Control Lists, Bootsplash, FS: SquashFS, FS: ramfs, Feature Freeze

People: Phillip LougherGreg KHWilly Tarreau

Phillip Lougher said:

I'm pleased to announce the release of Squashfs 2.1. This release introduces indexed directories which considerably speed up directory lookup (ls, find, etc.) for directories which are greater than 8K in size. All directories are now also sorted alphabetically which further speeds up directory lookup.

Many smaller improvements have also been made in this release, and there are, for the first time, the results of some tests of Squashfs lookup and I/O performance against Zisofs, Cloop, and CRAMFS.

For further details please go to the project page http://squashfs.sourceforge.net.

Willy Tarreau was very excited by all this, and said his own tests showed great performance results. He also pointed out that SquashFS wouldn't compile with GCC versions prior to version 3, and posted a small patch to address that issue. Phillip said he'd do another release, to take care of the compiler incompatibilities.

Elsewhere, Greg KH asked, "Are you going to submit this fs for inclusion in the main kernel tree? I'm getting tired of maintaining it as part of the Gentoo kernel patch set :)" Phillip replied:

Good question... When I originally released Squashfs (Oct 2002) the 2.5 kernel had just gone into the feature freeze and I was waiting for the unfreeze that would happen when 2.7 arrived. As the official stance on additions to 2.6 has been relaxed I have thought about submitting it.

I need to tidy up the code a bit before I submit it to the merciless scrutiny of LKML :-) Nothing bad (I hope) but there's lots of long lines and I do know LKML'mers like 80 columns.

I'm planning on adding ea/acl support (people have been asking for them), I can't decide whether to submit it now or wait until I've finished them. Suggestions and advice would be welcome.

Slightly off topic, I've noticed you're the kernel maintainer for Gentoo. You mentioned somewhere you're down to 4 kernel patches, including Squashfs? :) A lot of people/projects are now using Squashfs and it would help a lot of people (and me) if it did get into the kernel. Plus it would be a nice thing for me anyway to have finally got it included.

Greg urged Phillip to submit SquashFS now, because "it's self contained (doesn't patch anything outside it's own directory), and is useful in it's current state for a lot of people." Regarding SquashFS in Gentoo, Greg explained:

Yes, squashfs is one of the four non-bugfix patches in the Gentoo kernel 2.6 kernel package.

For those who are interested, the other three are:

Ok, there are now 5 patches, I forgot we addeed inotify recently to make the Gnome developers happy.

6. Linux 2.6.9-ac15 Released

11 Dec 2004 (1 post) Subject: "Linux 2.6.9-ac15"

Topics: Kernel Release Announcement

People: Alan CoxArjan van de Ven

Alan Cox announced Linux 2.6.9-ac15, saying:

Arjan van de Ven is now building RPMS of the kernel and those can be found in the RPM subdirectory and should be yum-able. Expect the RPMS to lag the diff a little as the RPM builds and tests do take time.

The HPT366 rework project is also not ready (its gone back to the drawing board until the current panic is over if you are a volunteer and wondered what is up).

ftp://ftp.kernel.org/pub/linux/kernel/people/alan/linux-2.6/2.6.9/

 

 

 

 

 

 

Sharon And Joy
 

Kernel Traffic is grateful to be developed on a computer donated by Professor Greg Benson and Professor Allan Cruse in the Department of Computer Science at the University of San Francisco. This is the same department that invented FlashMob Computing. Kernel Traffic is hosted by the generous folks at kernel.org. All pages on this site are copyright their original authors, and distributed under the terms of the GNU General Public License version 2.0.