Daily blurbs May. 2006


daily blurbs

29 May 2006 (Mon)

07:39:10 # Life tofu, as in emacs. After dist-upgrading to Xorg 7.0, I noticed many things broke. Emacs is looking like a tofu display. This sounds like a bad news. Another thing is that radeon driver doesn't seem to work, and I've reverted to vesa for now.

After a reboot, it now works. I've got radeon driver working, and even with acceleration. The fonts have come back also. Weird.

27 May 2006 (Sat)

17:55:06 # Life cowdancer and its limitations. I've been expecting a few design problems with cowdancer; and I was hoping that these problems are going to be minimal that normal package building isn't affected. One thing that cowdancer cannot handle is that because it plays tricks with replacing i-nodes when writing to a file, any application that expects same i-nodes before and after 'open' syscall will fail. Apparently, this is a popular behavior to avoid symlink attacks. So, if an application does lstat, open, fstat, in sequence, and checks the dev/inode number of the lstat/fstat result, the application will be confused when running under cowdancer, which will change the inode number hooking 'open'. For cowdancer with pbuilder, if dpkg/apt and preinst/postinst works, that's fine, and it seems to be functioning; which is good.

26 May 2006 (Fri)

06:43:20 # Life cowdancer and pbuilder. I've uploaded a new version of cowdancer and pbuilder, which work with each other. The two new extensiosn, cowbuilder command, and --pbuilder option (PDEBUILD_PBUILDER configuration option) to pdebuild, will allow cowdancing with pbuilder. Result of hacking at Debconf and in the plane back home. Enjoy.

22 May 2006 (Mon)

11:45:44 # Life debconf7 ends quietly. I'm in the hacklab, and there are quite a few people still left in hacklab. Logistically, this debconf had the conference rooms/hacklab/hotel rooms too far away from each other, and I found myself staying in one location. Swimming pool was a pleasant addition, but I couldn't utilise it when I suffered diarrhoea. Language was a very big problem, since the Hotel people did not understand a word of English (well, they sometimes pretended to understand a few words, but that was not enough to make them do what I wanted.).

Cost of living wasn't too low. The cost of everything within this Oaxtapec Hotel premises was around 50% higher than outside. Even in the outside, the cost wasn't as low as expected, but around 50% of what I would expect from Japan.

It apparently isn't a common practice to have a price tag around, so the price of most of the things on store are subject to negotiation.

Network was down for me most of the time, since there was no wirefull connection to the hotel rooms, or conference halls, and my wireless connection had some kind of kernel or hardware problem which meant I could not be connected for more than 5 minutes.

I had a few interesting work there, but I realized network is a very crucial part of hacking. The following should really be easily accessible offline: Debian mirror (yeah, I can mirror it, no probs), Debian BTS (I could rsync the whole beast), Wiki.debian.org (how?), and Version Control Systems (using git has solved most problems).

21 May 2006 (Sun)

01:25:18 # Life Biella's talk. Rather hard for me to follow, with difficult terminology repeated, with hard-to-follow content, with somewhat US-centric references to whatever Amendment made to whatever I don't recognise.

02:14:36 # Life Lightning talks. Coordinated by Joey Hess. Will we fit in?

02:23:36 # Life Updated libpkg-guide. I've made a major re-ordering of chapters. I'm looking at reducing some text from the document so that it's better organized.

03:13:42 # Life Debugging debacle by AJ and Erinn Clarke.

05:32:19 # Life debconf[67] BOF. Andreas Schuldei starts by complaining this is not the kind of setting he expected. It was not a BOF meant to be open to everyone.

20 May 2006 (Sat)

00:30:09 # Life i18n BOF. How the translation process should be governed.

On a different note, I've been analysing the dmesg messages on the wlan card. It looks like the messages are generated from linux-wlan-ng sources, something is returning -EIO when it's not really expected.

01:28:38 # Life About X and its history.

05:31:18 # Life shared library packaging by Josselin Mouette.

Required updates to libpkg-guide

19 May 2006 (Fri)

23:27:50 # Life Reviewing what keys are signed by me. To prepare for the keysigning party, I've reviewed what keys I have signed so far, and noticed that I have not signed anybody's key except for Japanese people. Which sounds more like a result of broken script rather than some intention...

17 May 2006 (Wed)

05:18:32 # Life Still fighting with my wireless setup. I've upgraded the kernel to, and tried again. However, it seems to pull the machine to a hard halt after a while. Hmm.. This is USB wlan device (GW-US11H) on iBook G4.

May 17 05:14:14 ibookg4 kernel: hfa384x_usbctlx_complete_sync: CTLX[3] error: state(Request failed)
May 17 05:14:14 ibookg4 kernel: prism2sta_commsqual_defer: error fetching commsqual
May 17 05:14:14 ibookg4 kernel: skb_p80211_to_ether: OTHER frame too large (2940 > 1500)
May 17 05:14:16 ibookg4 last message repeated 2 times
May 17 05:14:36 ibookg4 kernel: skb_p80211_to_ether: OTHER frame too large (-30 > 1500)
May 17 05:14:37 ibookg4 kernel: skb_p80211_to_ether: OTHER frame too large (2940 > 1500)
May 17 05:14:37 ibookg4 kernel: skb_p80211_to_ether: OTHER frame too large (-30 > 1500)
May 17 05:14:37 ibookg4 kernel: skb_p80211_to_ether: OTHER frame too large (2940 > 1500)
May 17 05:14:38 ibookg4 kernel: skb_p80211_to_ether: OTHER frame too large (-6 > 1500)

On the other hand, I found something is weird about my cpuinfo. bogomips of 36 doesn't sound quite right.

processor	: 0
cpu		: 7447A, altivec supported
clock		: 1066.666664MHz
revision	: 0.1 (pvr 8003 0101)
bogomips	: 36.73
timebase	: 18432000
machine		: PowerBook6,5
motherboard	: PowerBook6,5 MacRISC3 Power Macintosh 
detected as	: 287 (iBook G4)
pmac flags	: 0000001b
L2 cache	: 512K unified
pmac-generation	: NewWorld

I asked in the mailing list, and got answer from BenH and others that ppc moved on to using timebase instead of bogomips, and bogomips is no longer calculated.

16 May 2006 (Tue)

00:22:45 # Life wookey, BOF on embedded Debian. scratchbox 2, crossbuild.

03:09:28 # Life translation BOF.

05:40:07 # Life My wlan is dying quite often. It's a prism2 card. There seems to be some kind of error condition, and once it enters that condition, the number of error packets will just increase.

hfa384x_usbctlx_complete_sync: CTLX[3] error: state(Request failed)
prism2sta_commsqual_defer: error fetching commsqual
skb_p80211_to_ether: OTHER frame too large (2940 > 1500)
skb_p80211_to_ether: OTHER frame too large (2940 > 1500)
skb_p80211_to_ether: OTHER frame too large (2940 > 1500)
skb_p80211_to_ether: OTHER frame too large (2940 > 1500)

14 May 2006 (Sun)

21:56:08 # Life Fighting with wlan card. I'm trying to figure out why this Prism2 USB card is locking my system hard. Maybe I'll give up and use the wirefull network for the timebeing.

3 May 2006 (Wed)

01:20:37 # Life Wondering how to remove tempfiles. Since I'm so much annoyed by the current behaviour of cowdancer, I don't want to have .ilist file in the current directory. Instead I want to put it somewhere under /tmp. Current model of cowdancer execution is that it creates a file called .ilist in the current directory, and each session of application under cowdancer control will mmap that file. It might be better if I just dump something in /dev/shm, or /tmp which might even be memory-backed to alleviate the need for disk access. cow-shell execs the child session, and thus it's no longer available to remove the .ilist file when it's time to free it. .ilist file isn't that big, so leaving it in /tmp for later automatic removal by other means sounds feasible; I'm not too sure. SysV IPC shm routines with Linux extentions look a bit attractive, although I really dislike the arcane interface. Gives me the same sense of fear as when I look at X Toolkit programming. I wonder what's the current recommended way to go forward.

Pros Cons
A known filename in current directory Same file for multiple invocation from the same directory Hard to automatically detect the files no longer used, to mark them for deletion.
/dev/shm or /tmp Eventually automatically deleted by tmpreaper et al. Could be memory-backed. Multiple files can be generated for same directory under different names.
shmget/shmat Could be deleted when all attaching processes die when shm segment is marked for deletion. (Linux extention) Uses an arbitrary number as shm ID. Arcane interface with Linux-specific extensions, something to be left for good along with the fond memories of the 20th century?

Junichi Uekawa

$Id: 200605.html.en,v 1.22 2006/05/29 14:06:56 dancer Exp $