From: "Leyendecker, Robert" <Robert.Leyendecker@lsi.com>
To: Tim Blechmann <tim@klingt.org>
CC: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
       "linux-ext4@vger.kernel.org" <linux-ext4@vger.kernel.org>
Date: Sat, 28 Nov 2009 22:02:52 -0500
Subject: RE: ext4: smp_processor_id() in preemptible
Thread-Topic: ext4: smp_processor_id() in preemptible
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> -----Original Message-----
> From: Tim Blechmann [mailto:tim@klingt.org]
> Sent: Friday, November 27, 2009 4:33 AM
> To: Leyendecker, Robert
> Cc: linux-kernel@vger.kernel.org; linux-ext4@vger.kernel.org
> Subject: Re: ext4: smp_processor_id() in preemptible
> 
> > I have similar crash, but probably different cause-vector, posted on
> this list, fedora bugzilla, rt-users but no response so far from
> anyone. Did you find any work around?  I tried looking at smp code for
> hints on problem it looks like in my case it could be trying to
> reschedule work on different CPU at time of crash. However, I admit
> that I could be way, way off on that cause. In my case, if I hammer my
> network interface with packets while another app is reading packets, my
> host locks up and clients are reporting dest unreachables.
> >
> > I don't think I have the problem in non-rt kernel. Have you tried
> booting without smp support?
> 
> i haven't tried to reproduce it since then ... it occurred, when i was
> doing some heavy io tasks ...
> 
> tim
> 
> --
> tim@klingt.org
> http://tim.klingt.org
> 
> Nothing exists until or unless it is observed. An artist is making
> something exist by observing it. And his hope for other people is that
> they will also make it exist by observing it. I call it 'creative
> observation.' Creative viewing.
>   William S. Burroughs

OK - thanks. I'm arriving here via heavy network io, relatively easy to repro in my case.

-Bob
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