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Date: Fri, 23 Jan 2015 14:54:11 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Sasha Levin <sasha.levin@oracle.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        "davej@codemonkey.org.uk >> Dave Jones" <davej@codemonkey.org.uk>
Subject: Re: rcu, sched: WARNING: CPU: 30 PID: 23771 at
 kernel/rcu/tree_plugin.h:337 rcu_read_unlock_special+0x369/0x550()
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On Fri, Jan 23, 2015 at 04:51:52PM -0500, Sasha Levin wrote:
> On 01/23/2015 04:36 AM, Paul E. McKenney wrote:
> > diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
> > index 8669de884445..ec99dc16aa38 100644
> > --- a/kernel/rcu/tree_plugin.h
> > +++ b/kernel/rcu/tree_plugin.h
> > @@ -322,6 +322,7 @@ void rcu_read_unlock_special(struct task_struct *t)
> >  	special = t->rcu_read_unlock_special;
> >  	if (special.b.need_qs) {
> >  		rcu_preempt_qs();
> > +		t->rcu_read_unlock_special.need_qs = false;
> 
> It didn't compile, I've used:
> 
> 		t->rcu_read_unlock_special.b.need_qs = false;

Apologies, I should have marked it "untested".  Good show on finding
the correct fix.

But does your fixed version help?  ;-)

							Thanx, Paul