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Date: Thu, 28 Sep 2017 16:51:46 -0700
From: Govindarajulu Varadarajan <gvaradar@cisco.com>
To: Peter Zijlstra <peterz@infradead.org>
CC: <benve@cisco.com>, <bhelgaas@google.com>, <linux-pci@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <jlbec@evilplan.org>, <hch@lst.de>,
        <mingo@redhat.com>
Subject: Re: [PATCH 4/4] lockdep: make MAX_LOCK_DEPTH configurable from
 Kconfig
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On Thu, 28 Sep 2017, Peter Zijlstra wrote:

> On Wed, Sep 27, 2017 at 02:42:20PM -0700, Govindarajulu Varadarajan wrote:
>> Make MAX_LOCK_DEPTH configurable. It is set to 48 right now. Number of
>> VFs under a PCI pf bus can exceed 48 and this disables lockdep.
>>
>> lockdep currently allows max of 63 held_locks.
>
> But why a config knob? Why not just raise the number to 64
> unconditionally? And is that sufficient; you only state 48 is
> insufficient, you don't actually state the VF limit.
>

I did not want to change the default configuration for everyone.

I will change it 63 unconditionally in v2 and resubmit the series.