unsigned long geek = random();

I just received this in a mail from the publishers of Linux Journal:

For a limited time all international subscriptions to the print edition of Linux Journal will be reduced to the low price of $49.50 for 1 year (a savings of over 30% off the regular price) AND upgraded to include a free digital subscription. As a special bonus you will also receive Linux Journal’s System Administration Special Issue free of charge.

I’ve been a Linux Journal subscriber since the late 90s and can recommend it as one of the better general-interest computer publications. To take advantage of the special offer, visit the Linux Journal site. It seems the promo code to take part in this offer is M96INTL.

Update: Fixed the link to the subscription page, courtesy of Mark at Linux Journal. Whoops!

A few days ago I upgraded the Ubuntu partition on my HP Mini-Note 2133 from 8.10 to the release candidate of 9.04 (i386). The upgrade itself went very smoothly, for the most part – I ran Update Manager, answered a few questions and waited for the upgrade to complete. With the fairly pedestrian 1.2Ghz VIA C7 CPU the upgrade took around an hour and a half.

When I rebooted, I spotted the first problem – GRUB presented me with the kernels from 8.10 (2.6.27.*) but not the 9.04 kernel (2.6.28.*). During the installation I had elected not to overwrite GRUB’s menu.lst, thinking that it would still get updated when the kernel package was configured. Oddly, that didn’t happen. My solution was to edit /boot/grub/menu.lst and add entries for the 9.04 default kernel (doing a dpkg-reconfigure on the kernel package would probably also have fixed it).

Once I had booted the correct kernel, I tackled the second problem – X didn’t work. With 8.10 I had been using the proprietary VIA DRM kernel module, which enabled hardware-accelerated 3D on the 2133′s Chrome9 chipset, but it didn’t work with the updated 9.04 kernel. I moved my /etc/X11/Xorg.conf out of the way and restarted X, which then started correctly with sane defaults (newer releases of X.Org no longer require a configuration file). Rather pleasingly, the OpenChrome driver being used by X.Org started with the correct 1280×768 resolution. The one downside of not using the VIA module is that compiz et al. don’t work – not a big issue for now and one that should be rectified once VIA update their DRM kernel module for 9.04′s kernel. One possible workaround is to boot the most recent kernel from 8.10 (which is still installed), but I haven’t tried that yet.

The third problem, and the most annoying, relates to the 2133′s Broadcom wireless. With 8.10 I had been using ndiswrapper and it worked perfectly. For some reason, as soon as I tried to connect to my home wireless network after upgrading to 9.04, WPA authentication failed (I kept getting prompted for my key and the key I entered was never saved). I then switched to using the Broadcom STA driver, which authenticates successfully, but exhibits a few problems of its own – it often looses the connection to my access point and sometimes doesn’t work correctly after resuming from a suspend. I’m going to switch back to using ndiswrapper to see if it’ll work with a bit more coaxing.

Overall, I’m reasonably happy with the upgrade – other than the issues mentioned above, it went smoothly and the system is working well. The only issue that’s really causing me pain at the moment is the wireless (but then it is Broadcom…).

A few months ago while working on a Linux system using XFS, I came across an interesting “feature”. When moving a directory such that its owner changed, the moved directory’s mtime was changed to the current date and time.

For example:

[0] mj@majestic:~/tmp$ mount |grep home
/dev/mapper/data-home on /home type xfs (rw)
[0] mj@majestic:~/tmp$ mkdir test
[0] mj@majestic:~/tmp$ ls -ld test
drwxr-sr-x 2 mj mj 6 Jun 18 15:28 test
[0] mj@majestic:~/tmp$ touch -t 200801011530 test
[0] mj@majestic:~/tmp$ ls -ld test
drwxr-sr-x 2 mj mj 6 Jan 1 15:30 test
[0] mj@majestic:~/tmp$ stat test
File: `test'
Size: 6 Blocks: 0 IO Block: 4096 directory
Device: fd00h/64768d Inode: 951267331 Links: 2
Access: (2755/drwxr-sr-x) Uid: ( 1000/ mj) Gid: ( 1000/ mj)
Access: 2008-01-01 15:30:00.000000000 +0000
Modify: 2008-01-01 15:30:00.000000000 +0000
Change: 2008-06-18 15:29:08.173750666 +0100
[0] mj@majestic:~/tmp$ mv test test1
[0] mj@majestic:~/tmp$ ls -ld test1
drwxr-sr-x 2 mj mj 6 Jan 1 15:30 test1
[0] mj@majestic:~/tmp$ mv test1 ..
[0] mj@majestic:~/tmp$ ls -ld ../test1
drwxr-sr-x 2 mj mj 6 Jun 18 15:30 ../test1
File: `../test1'
Size: 6 Blocks: 0 IO Block: 4096 directory
Device: fd00h/64768d Inode: 951267331 Links: 2
Access: (2755/drwxr-sr-x) Uid: ( 1000/ mj) Gid: ( 1000/ mj)
Access: 2008-01-01 15:30:00.000000000 +0000
Modify: 2008-06-18 15:30:02.814078187 +0100
Change: 2008-06-18 15:30:02.814078187 +0100


I’d never seen this happen before, so I tried to reproduce the behaviour on systems using ext3, UFS and HFS+ filesystems. None of them updated the moved directory’s mtime when the parent directory changed, which is what one would expect. XFS does have an active mailing list, so I reported my findings and was quickly provided with a patch that fixed the problem. Kudos to the XFS developers for providing a fix so quickly.

Rather odd that no-one had spotted this behaviour in the past though…

I’ve obviously been living in a cave for a while, but I only recently discovered that Panix are offering “virtual colocation” via Xen virtual machines. One very nice feature – they offer NetBSD in addition to the customary Linux. Pricing is competitive and they also offer a free backup service, which is a nice addition. Not quite sure why their default NetBSD virtual machine includes X11 though?

I upgraded my notebook to Linux kernel 2.6.18 about a month ago, shortly it was released. One thing that is greatly improved is the stability of suspending to disk. I use Suspend 2 and with various patchlevels of 2.6.17 it would sometimes not suspend properly, necessitating a reboot. Things seem a lot better after the upgrade – I haven’t yet had a suspend fail, touch wood.

Sadly, my laptop still generates spurious ACPI overheating events, which cause an unwanted shutdown. That’s something I’ll probably have to fix with a new DSDT or by patching the kernel myself to ignore nonsensical temperatutes (783 degrees!).

Today I upgraded to VMware Workstation 5.5.2 on my notebook, which runs Debian testing. When I started VMware, I got the following in a terminal window, but the VMware window didn’t appear:

/usr/local/lib/vmware/bin/vmware: /usr/local/lib/vmware/lib/libpng12.so.0/libpng12.so.0: no version information available (required by /usr/lib/libcairo.so.2)
/usr/local/lib/vmware/bin/vmware: /usr/local/lib/vmware/lib/libpng12.so.0/libpng12.so.0: no version information available (required by /usr/lib/libcairo.so.2)


After a bit of judicious Googling, it seems that the above libpng errors are red herrings and that the problem is caused by an incorrect libdbus being loaded by VMware. The solution is to preload the correct version of libdbus. For more information, including a solution, see this thread on the VMware forums. Apparently newer versions of Ubuntu exhibit the same problem.

As Rafiq says, our local LUG is in need of sponsorship for its stand at this year’s Futurex exhibition. About half the money needed (R10,000 – about US$ 1,250) has been collected so far, but we still need every donation we can get. For more info on donating, see the sponsorship page on the CLUG site.

I’ve made my donation (guess who I am on the list – have you?

I see that Sun were offering a reward for the porting of Linux to their CoolThreads-based systems (a reward I’m sure has been claimed now that David S. Miller has Linux booting multi-user on such systems). Come on Sun – why not offer the same reward for porting NetBSD to CoolThreads? After all, SunOS releases prior to 5.x were based on BSD and Sun has made past donations to The NetBSD Foundation.