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Date:   Fri, 11 Mar 2022 12:08:14 +0100
From:   Frederic Weisbecker <frederic@kernel.org>
To:     "Paul E. McKenney" <paulmck@kernel.org>
Cc:     linux-kernel@vger.kernel.org
Subject: Re: Scenario TREE07 with CONFIG_PREEMPT_DYNAMIC=n?
Message-ID: <20220311110814.GA96127@lothringen>
References: <20220310215630.GA3490034@paulmck-ThinkPad-P17-Gen-1>
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On Thu, Mar 10, 2022 at 01:56:30PM -0800, Paul E. McKenney wrote:
> Hello, Frederic,
> 
> I recently added CONFIG_PREEMPT_DYNAMIC=n to the TREE07 file, and since
> then am getting roughly one RCU CPU stall warning (or silent hang)
> per few tens of hours of rcutorture testing on dual-socket systems.
> The stall warnings feature starvation of RCU grace-period kthread.
> 
> Any advice on debugging this?
> 
> 							Thanx, Paul

Ok it reproduces easily but I have no clue about the origin. I'm starting a
bisection.

Thanks!