kernel hang running strace on cupsd

[Richard Mortimer <richm@oldelvet.org.uk>]

Hi,

Whilst trying to debug the Cups problem that I just sent out in
another mail I came across a kernel hang on sparc64. I'm running
Debian kernel-image-2.6.8-1-sparc64

I was running an strace on the cupsd process i.e.


shirehall:~# strace -p 2067
Process 2067 attached - interrupt to quit
select(1024, [0 2 3], [], NULL, {22, 13000} <unfinished ...>
Process 2067 detached
shirehall:~#

Now all I did was to start a printer using the "Start Printer" button
from the cups web interface.

At this point the system just hung solid. I couldn't ping the box. The
console was not responsive. I could send a break (serial console only)
and get to the ok prompt but usual suspects go, sync or ctrace didn't
help. I reproduced this a few times.

Is there anything else that I can do to get some debug information out
of the system.

I haven't tried the latest kernel sources (I don't have time to do so
at the moment) so this may be an already fixed issue. If no-one has
seen this before I'll try to find some time next week to take a closer
look.

Richard

richm@oldelvet.org.uk