lkml.org 
[lkml]   [2009]   [Apr]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [BUG] 2.6.29.1 debugobjects warning
* Ingo Molnar (mingo@elte.hu) wrote:
>
> * Andrew Morton <akpm@linux-foundation.org> wrote:
>
> > On Thu, 23 Apr 2009 10:00:02 -0400
> > Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> wrote:
> >
> > > ODEBUG: init active object type: timer_list
>
> > It seems to be complaining that cpufreq_governor_dbs() is running
> > init_timer() against a timer which has already been initialised
> > once.
>
> Not just already initialized - but also active. There's these states
> for an object:
>
> ODEBUG_STATE_NONE,
> ODEBUG_STATE_INIT,
> ODEBUG_STATE_INACTIVE,
> ODEBUG_STATE_ACTIVE,
> ODEBUG_STATE_DESTROYED,
>
> So the 'init active object type' warning above suggests that an
> init_timer() has been done on an already running timer. If true then
> that is a bad bug - can corrupt timer state, etc.
>
> Thomas, do you agree?
>

This would fit with the behavior I've noticed and submitted a patch for
later in this thread. Basically, the incorrect use of
"cancel_delayed_work()" instead of "cancel_delayed_work_sync()" may
leave the timer active if the race explained in the mail below happen.

http://lkml.org/lkml/2009/4/24/19

Maybe we should audit other users of
schedule_delayed_work/cancel_delayed_work that are re-arming themselves
in the workqueue handler without any proper cancel_delayed_work_sync()
nor flush_workqueue() calls on teardown.

Mathieu

> Ingo

--
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68


\
 
 \ /
  Last update: 2009-04-24 17:11    [W:0.064 / U:0.956 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site