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Date:   Fri, 13 Dec 2019 22:40:48 -0800
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Qian Cai <cai@lca.pw>
Cc:     "Joel Fernandes (Google)" <joel@joelfernandes.org>,
        Tejun Heo <tj@kernel.org>,
        Josh Triplett <josh@joshtriplett.org>,
        Steven Rostedt <rostedt@goodmis.org>, rcu@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: "rcu: React to callback overload by aggressively seeking
 quiescent states" hangs on boot
Message-ID: <20191214064048.GI2889@paulmck-ThinkPad-P72>
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References: <20191213224646.GH2889@paulmck-ThinkPad-P72>
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On Fri, Dec 13, 2019 at 06:11:16PM -0500, Qian Cai wrote:
> 
> 
> > On Dec 13, 2019, at 5:46 PM, Paul E. McKenney <paulmck@kernel.org> wrote:
> > 
> > I am running this on a number of x86 systems, but will try it on a
> 
> The config to reproduce includes several debugging options that might
> required to recreate.

If you run without those debugging options, do you still see the hangs?
If not, please let me know which debugging are involved.

> > wider variety.  If I cannot reproduce it, would you be willing to
> > run diagnostics?
> 
> Yes.

Very good!  Let me see what I can put together.  (No luck reproducing
at my end thus far.)

> > Just to double-check...  Are you running rcutorture built into the kernel?
> > (My guess is "no", but figured that I should ask.)
> 
> No as you can see from the config I linked in the original email.

Fair point, and please accept my apologies for the pointless question.

							Thanx, Paul