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Date: Thu, 16 Apr 2015 17:35:03 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Andreas Messerschmid <andreas@linutronix.de>
Subject: Re: [PATCH] lockdep: make print_lock_name() robust against
 non-existing lock_class
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On Thu, Apr 16, 2015 at 04:50:21PM +0200, Sebastian Andrzej Siewior wrote:

> Andreas confirmed that it works for him on v3.18 with minor adjustment.
> 
> <---
> +       struct held_lock lock = READ_ONCE(*hlock);
> +       unsigned int class_idx = lock.class_idx;
> --->
> 

I'm confused by the need for that. What was the failure with the
proposed patch?