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Date: Sun, 27 Mar 2016 22:53:18 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        "Chatre, Reinette" <reinette.chatre@intel.com>,
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Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17
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On Sun, Mar 27, 2016 at 08:40:18AM -0700, Paul E. McKenney wrote:
> Oh, and the patch I am running with is below.  I am running x86, and so
> some other architectures would of course need the corresponding patch
> on that architecture.

> -#define TIF_POLLING_NRFLAG	21	/* idle is polling for TIF_NEED_RESCHED */

Also note that ARM (v7) which Ross is running doesn't have this to begin
with.