Re: [BUG] local_softirq_pending storm

["Michal Piotrowski" <michal.k.k.piotrowski@gmail.com>]

Hi Thomas,

On 20/05/07, Thomas Gleixner <tglx@linutronix.de> wrote:
> On Sun, 2007-05-20 at 02:53 +0530, Anant Nitya wrote:
> > > 1 == TASK_INTERRUPTIBLE, so we know that ksoftirqd was not woken up. At
> > > least it is not a scheduler problem.
> > >
> > > I work out a more complex debug patch and pester you to test once I'm
> > > done.
> > No problem :)
>
> You asked for it :)
>
> Please patch 2.6.22-rc2 with
>
> http://tglx.de/projects/hrtimers/2.6.22-rc2/patch-2.6.22-rc2-hrt2.patch
> and
> http://www.tglx.de/private/tglx/ht-debug/tracer.diff
>
> Compile it with the config
>
> http://www.tglx.de/private/tglx/ht-debug/config.debug
>
> You should find something like:
>
> (         swapper-0    |#0): new 67173 us user-latency.
>
> along with the familiar "NOHZ ......" message in your log file.
>
> Once that happened please do:
>
> $ cat /proc/latency_trace >trace.txt
>
> compress it and send it to me along with the full dmesg output or put
> both up to some place, where I can download it.
>
> Michal,
>
> IIRC you encountered the same P4/HT related wreckage. Can you do the
> same ?

Good news - I can't reproduce this bug. It's time to remove
"Subject    : 2.6.21-git4 BUG: soft lockup detected on CPU#1!
References : http://lkml.org/lkml/2007/5/2/511
Submitter  : Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Handled-By : Thomas Gleixner <tglx@linutronix.de>
Status     : problem is being debugged"
from KR.

Bad news - I hit a bug in 2.6.22-rc2-hrt3. Bug symptoms:
- X hangs (keyboard, mouse, sound etc.)
- only Magic SysRq works

http://www.stardust.webpages.pl/files/tbf/bitis-gabonica/2.6.22-rc2-hrt3/hrt-config
http://www.stardust.webpages.pl/files/tbf/bitis-gabonica/2.6.22-rc2-hrt3/hrt-console.log

Now I'm trying to apply hrtimers debug patch ontop 2.6.22-rc2-hrt3
http://lkml.org/lkml/2007/3/23/106

Regards,
Michal

-- 
Michal K. K. Piotrowski
Kernel Monkeys
(http://kernel.wikidot.com/start)