sem_wait: Function not implemented on a debian-chroot on a mipsel-router

[markus.doits@…]

hello,

well, i think this will be a difficult one, since i have a very special setup:

my router (a fritz-box) is running the following kernel:

Linux fritz.fonwlan.box 2.6.19.2 #10 Fri Jun 12 10:59:30 CEST 2009 mips GNU/Linux

this is a kernel hacked by the developers, sources are available and can be compiled (though no .config available). an older version (not the one i'm using now) is available here: ​ftp://ftp.avm.de/develper/opensrc/fritzbox-source-files-04.70.tar.gz. the newer one should be released soon when the new firmware is officially released.

on this box i've got a debian-mipsel chroot (lenny). proc, sys are mounted and dev is mounted with "-o bind /dev /path/to/chroot/dev".

lighttpd, sqlite3, php5 (and basic debian packages like ssh) are working, so i tried to setup trac. installed it the debian-way (aptitude) and successfully created a repro (imported from an svn-repro). tracd starts too, but as soon as someone visits the site:

fritz:/srv/trac# tracd --port 8000 /srv/trac/
Server starting in PID 12926.
Serving on 0.0.0.0:8000 view at http://127.0.0.1:8000/
127.0.0.1 - - [13/Jun/2009 23:52:19] "GET / HTTP/1.1" 200 -
127.0.0.1 - - [13/Jun/2009 23:52:19] "GET /favicon.ico HTTP/1.1" 404 -
127.0.0.1 - - [13/Jun/2009 23:52:22] "GET /favicon.ico HTTP/1.1" 404 -
sem_wait: Function not implemented
Segmentation fault

okey, thought this might be a special error with tracd, and since lighttpd is working, i tried to setup trac with it like stated on TracFastCgi. unfortunately, no response accessing the site and in error.log (lighttpd):

sem_wait: Function not implemented
2009-06-14 00:10:59: (mod_fastcgi.c.2489) unexpected end-of-file (perhaps the fastcgi process died): pid: 16108 socket: unix:/tmp/trac-fastcgi.sock-3 
2009-06-14 00:10:59: (mod_fastcgi.c.3256) child signaled: 11 
2009-06-14 00:10:59: (mod_fastcgi.c.3299) response not received, request sent: 869 on socket: unix:/tmp/trac-fastcgi.sock-3 for /trac , closing connection 

so now i'm not sure - is this a kernel problem, because it's an old modified one? is it a mipsel-bug? or is trac in lenny simply broken?

did not try to install debug-symbols yet and make a gdb-backtrace (since it takes ages to install it on this 120mhz-cpu with 64mb ram :) ), but i will do it tomorow when you say this may help!

any chance to get this running? or is this setup too special?

thanks for your help

[ebray]

What version of Python are you using? What happens if you try to open the Trac environment without going through a web server? python -c "from trac.env import open_environment; open_environment(/path/to/env)"

Regardless, I'd be surprised if this is a problem on Trac's end.

[Christian Boos]

Looks like sem_wait is only used in Python/thread.o, so maybe you can avoid the problem with this apparently unimplemented system call by not using threads (e.g. in tracd, using the change suggested here: ticket:2598#comment:8).

[markus.doits@…]

fritz:/usr/share/pyshared/trac/web# python --version
Python 2.5.2

but i changed the line like ticket:2598#comment:8 suggested and it works, thanks! so for now i am happy (however it is slow as hell, but i did not expect anything better from that router).

thanks, regards

[Christian Boos]

Thanks for the feedback!