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Date:   Mon, 25 Jun 2018 18:16:38 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Andy Lutomirski <luto@kernel.org>
Cc:     "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        joel@joelfernandes.org, Byungchul Park <byungchul.park@lge.com>,
        byungchul park <max.byungchul.park@gmail.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Josh Triplett <josh@joshtriplett.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        LKML <linux-kernel@vger.kernel.org>, kernel-team@lge.com
Subject: Re: [RFC 2/2] rcu: Remove ->dynticks_nmi_nesting from struct
 rcu_dynticks
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On Mon, 25 Jun 2018 13:47:45 -0700
Andy Lutomirski <luto@kernel.org> wrote:

> 
> As a straightforward example, NMI and MCE can nest inside each other.

But I'm not sure how stable the machine becomes when MCE's start
interrupting NMIs. Also, can MCE callbacks use RCU?

> IIRC we treat #DB somewhat NMI-ish-ly as well.

And #DB is something I think we finally said shouldn't be done in NMIs,
IIRC.

-- Steve