lkml.org 
[lkml]   [2007]   [Apr]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH -mm] workqueue: debug possible endless loop in cancel_rearming_delayed_work
Jarek Poplawski wrote:
> Hi,
>
> IMHO cancel_rearming_delayed_work is dangerous place:
>
> - it assumes a work function always rearms (with no exception),
> which probably isn't explained enough now (but anyway should
> be checked in such loops);
>
> - probably possible (theoretical) scenario: a few work
> functions rearm themselves with very short, equal times;
> before flush_workqueue ends, their timers are already
> fired, so cancel_delayed_work has nothing to do.
>
> Maybe this patch could check, if I'm not dreaming...
>
> PS: of course the counter value below is a question of taste

Okay, an easy test for it: insmod netconsole ; rmmod netconsole

In 2.6.20.x it loops forever and cancel_rearming_delayed_work()
is part of the trace...

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-04-19 19:15    [W:0.075 / U:0.108 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site