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Subject: Re: v3.0: Weird kernel log message when resuming avout NMI received
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Cyrill Gorcunov <gorcunov@gmail.com>
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Date: Mon, 01 Aug 2011 14:12:34 +0200
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On Mon, 2011-08-01 at 15:21 +0400, Cyrill Gorcunov wrote:
> >       mutex_lock(&swhash->hlist_mutex);
> > -     if (swhash->hlist_refcount > 0) {
> > +     if (swhash->hlist_refcount > 0 && !swhash->swevent_hlist) {
> 
> Should not there be rcu_dereference(swhash->swevent_hlist)? 

swhash->hlist_mutex is the modifier lock for that rcu use and should
thus serialize things sufficiently.