Subject: Re: Soft-Lockup/Race in networking in 2.6.31-rc1+195 ( possibly?caused by netem)

From: Andres Freund <[email-masked]>
Date: Thu, 9 Jul 2009 00:23:17 +0200

On Wednesday 08 July 2009 10:08:52 Jarek Poplawski wrote:
> On Tue, Jul 07, 2009 at 06:11:27PM +0200, Andres Freund wrote:
> > On Tuesday 07 July 2009 15:57:42 Jarek Poplawski wrote:
> > > On Tue, Jul 07, 2009 at 03:34:07PM +0200, Andres Freund wrote:
> > > ...
> > >
> > > > Testing wether its triggerable inside a vm might be interesting...
> > >
> > > Probably similarly to testing without this patch or even less. Maybe
> > > I should've warned you but this type of bugs in -rc with possible
> > > memory or stack overwrites might be fatal for your data (at least).
> >
> > Fortunately all the data on that machine should either be replaceable or
> > regularly backuped.
> >
> > Will test later today if that patch bugs.
>
> If you didn't start yet, it would be nice to use this, btw:
> CONFIG_HOTPLUG_CPU = N
> CONFIG_DEBUG_OBJECTS = Y
> CONFIG_DEBUG_OBJECTS_TIMERS = Y
Unfortunately this just yields the same backtraces during softlockup and not 
earlier.
I did not test without lockdep yet, but that should not have stopped the BUG 
from appearing, right?

Andres