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From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Milan Broz <mbroz@redhat.com>
Subject: Re: SwSusp to disk doesn't work - Try 2
Date: Sun, 11 Mar 2007 21:32:32 +0100
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Cc: Thomas Meyer <thomas@m3y3r.de>, linux-kernel@vger.kernel.org,
       Pavel Machek <pavel@ucw.cz>, Thomas Gleixner <tglx@linutronix.de>
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On Sunday, 11 March 2007 21:23, Milan Broz wrote:
> Rafael J. Wysocki:
> > Ah, NO_HZ.  Thomas Gleixner's address added to the Cc list.
> > 
> >> short printk trace 
> >>
> >> enable_nonboot_cpus
> >>  _cpu_up
> >>   raw_notifier_callchain (CPU_UP_PREPARE)
> >>     ...
> >>     update_sched_domains
> >>      detach_destroy_domains
> >>        [waits here] --> synchronize_sched (==synchronize_rcu)
> > 
> > Well, I think the call to wait_for_completion() does not return, probably
> > because the task supposed to complete the completion is frozen at this
> > point.  Can you please try to confirm that it gets stuck on
> > wait_for_completion() in synchronize_rcu()?
> 
> Yes, it's in wait_for_completion() in synchronize_rcu().
> As noted in some previous mail, it will wake up after
> event - key press etc.
> 
> Patch in http://lkml.org/lkml/2007/3/7/255 solves different problem.
> I added it to my quilt and applied anyway -> no change.

Does the problem go away if NO_HZ is unset?

Rafael