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Date:   Fri, 13 Sep 2019 18:04:17 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        paulmck <paulmck@linux.ibm.com>, Ingo Molnar <mingo@kernel.org>,
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        Chris Lameter <cl@linux.com>, Kirill Tkhai <tkhai@yandex.ru>,
        Mike Galbraith <efault@gmx.de>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [RFC PATCH 4/4] Fix: sched/membarrier: p->mm->membarrier_state
 racy load (v2)
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On 09/13, Mathieu Desnoyers wrote:
>
> membarrier_exec_mmap(), which seems to be affected by the same problem.

IIRC, in the last version it is called by exec_mmap() undef task_lock(),
so it should fine.

Oleg.