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Date: Fri, 2 Feb 2018 20:55:06 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Mark Rutland <mark.rutland@arm.com>
Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        efault@gmx.de, tglx@linutronix.de, mingo@kernel.org,
        alexander.levin@verizon.com
Subject: Re: Runqueue spinlock recursion on arm64 v4.15
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On Fri, Feb 02, 2018 at 07:27:04PM +0000, Mark Rutland wrote:
> ... in some cases, owner_cpu is -1, so I guess we're racing with an
> unlock. I only ever see this on the runqueue locks in wake up functions.

So runqueue locks are special in that the owner changes over a contex
switch, maybe something goes funny there?