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Date:   Sat, 29 Jun 2019 20:21:32 +0200
From:   Andrea Parri <andrea.parri@amarulasolutions.com>
To:     "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Byungchul Park <byungchul.park@lge.com>,
        Scott Wood <swood@redhat.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        rcu <rcu@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Josh Triplett <josh@joshtriplett.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>
Subject: Re: [RFC] Deadlock via recursive wakeup via RCU with threadirqs
Message-ID: <20190629182132.GA5666@andrea>
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> Remark: we do have code which (while acknowledging that "interrupts are
> synchronization points") doesn't quite seem to "believe it", c.f., e.g.,
> kernel/sched/membarrier.c:ipi_mb().  So, I guess the follow-up question
> would be "Would we better be (more) paranoid? ..."

should have been "IPIs are serializing" (so all a different "order"...)

  Andrea