Re: 2.6.24 regression: pan hanging unkilleable and un-straceable

[Ingo Molnar <mingo@elte.hu>]

* Nick Piggin <nickpiggin@yahoo.com.au> wrote:

> On Tuesday 22 January 2008 07:58, Frederik Himpe wrote:
> > With Linux 2.6.24-rc8 I often have the problem that the pan usenet
> > reader starts using 100% of CPU time after some time. When this happens,
> > kill -9 does not work, and strace just hangs when trying to attach to
> > the process. The same with gdb. ps shows the process as being in the R
> > state.
> >
> > I pressed Ctrl-Alt-SysRq-T, and this was shown for pan:
> > Jan 21 21:45:01 Anastacia kernel: pan           R  running task        0 
> 
> Well I've twice tried to submit a patch to print stacks for running 
> tasks as well, but nobody seems interested. It would at least give a 
> chance to see something.

i definitely remembering having done this myself a couple of times (it 
makes tons of sense to get _some_ info out of the system) but some 
problem in -mm kept reverting it. I dont remember the specifics ... it 
was some race.

	Ingo