From mboxrd@z Thu Jan  1 00:00:00 1970
From: Greg KH <greg@kroah.com>
Subject: Re: Re: lockdep report in hibernate code
Date: Wed, 24 Oct 2007 14:57:15 -0700
Message-ID: <20071024215715.GA9524@kroah.com>
References: <Pine.LNX.4.44L0.0710231750370.21581-100000@netrider.rowland.org>
	<200710240018.02655.rjw@sisk.pl>
	<1193215220.4097.8.camel@johannes.berg>
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To: Johannes Berg <johannes@sipsolutions.net>
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On Wed, Oct 24, 2007 at 10:40:20AM +0200, Johannes Berg wrote:
> On Wed, 2007-10-24 at 00:18 +0200, Rafael J. Wysocki wrote:
> 
> > Yes, which is what I think is happening in this particular case.  More
> > precisely, we get pm_mutex while holding a buffer mutex, so lockdep is warning
> > when we get another buffer mutex afterwards.
> 
> Precisely. That's why I copied Greg on the second mail :) It seems that
> sysfs already uses nested locks, but that only protects against lockdep
> reporting a false positive for nested locks, not this case.

Ok, I'm confused, where is the sysfs issue here?

thanks,

greg k-h