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Date: Tue, 28 Feb 2017 13:49:06 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Byungchul Park <byungchul.park@lge.com>
Cc: mingo@kernel.org, tglx@linutronix.de, walken@google.com,
        boqun.feng@gmail.com, kirill@shutemov.name,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, npiggin@gmail.com
Subject: Re: [PATCH v5 06/13] lockdep: Implement crossrelease feature
Message-ID: <20170228124906.GC32474@worktop>
References: <1484745459-2055-1-git-send-email-byungchul.park@lge.com>
 <1484745459-2055-7-git-send-email-byungchul.park@lge.com>
 <20170228124507.GG5680@worktop>
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On Tue, Feb 28, 2017 at 01:45:07PM +0100, Peter Zijlstra wrote:
> On Wed, Jan 18, 2017 at 10:17:32PM +0900, Byungchul Park wrote:
> > +	/*
> > +	 * struct held_lock does not have an indicator whether in nmi.
> > +	 */
> > +	int nmi;
> 
> Do we really need this? Lockdep doesn't really know about NMI context,
> so its weird to now partially introduce it.

That is, see how nmi_enter() includes lockdep_off().

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Date: Tue, 28 Feb 2017 13:49:06 +0100
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH v5 06/13] lockdep: Implement crossrelease feature
Message-ID: <20170228124906.GC32474@worktop>
References: <1484745459-2055-1-git-send-email-byungchul.park@lge.com>
 <1484745459-2055-7-git-send-email-byungchul.park@lge.com>
 <20170228124507.GG5680@worktop>
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To: Byungchul Park <byungchul.park@lge.com>
Cc: mingo@kernel.org, tglx@linutronix.de, walken@google.com, boqun.feng@gmail.com, kirill@shutemov.name, linux-kernel@vger.kernel.org, linux-mm@kvack.org, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org, npiggin@gmail.com

On Tue, Feb 28, 2017 at 01:45:07PM +0100, Peter Zijlstra wrote:
> On Wed, Jan 18, 2017 at 10:17:32PM +0900, Byungchul Park wrote:
> > +	/*
> > +	 * struct held_lock does not have an indicator whether in nmi.
> > +	 */
> > +	int nmi;
> 
> Do we really need this? Lockdep doesn't really know about NMI context,
> so its weird to now partially introduce it.

That is, see how nmi_enter() includes lockdep_off().

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