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Date: Fri, 5 Feb 2016 08:19:26 +0530
From: Viresh Kumar <viresh.kumar@linaro.org>
To: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Cc: Juri Lelli <juri.lelli@arm.com>, Rafael Wysocki <rjw@rjwysocki.net>,
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        linux-kernel@vger.kernel.org
Subject: Re: [PATCH V2 0/7] cpufreq: governors: Fix ABBA lockups
Message-ID: <20160205024926.GD3068@vireshk>
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On 05-02-16, 02:20, Shilpasri G Bhat wrote:
> I could see the previous lockdep warnings on pm/next and on top of patch[4].
> On Patch[5-7] I see the below lockdep trace on running './runme' on a Power8 box.

> [  710.336130] Chain exists of:
>   s_active#91 --> &dbs_data->mutex --> od_dbs_cdata.mutex
> 
> [  710.336376]  Possible unsafe locking scenario:
> 
> [  710.336488]        CPU0                    CPU1
> [  710.336577]        ----                    ----
> [  710.336666]   lock(od_dbs_cdata.mutex);
> [  710.336778]                                lock(&dbs_data->mutex);
> [  710.336911]                                lock(od_dbs_cdata.mutex);
> [  710.337064]   lock(s_active#91);
> [  710.337176]

This is the same lockdep, just that we have added another mutex
(dbs_data->mutex) to it.

Have you tried if all the lockdeps go away with the 8th patch that I
provided yesterday ?

-- 
viresh