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Date: Mon, 20 Nov 2017 10:49:27 -0800
From: Andi Kleen <andi@firstfloor.org>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
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        Michael Kerrisk <mtk.manpages@gmail.com>
Subject: Re: [RFC PATCH v3 for 4.15 08/24] Provide cpu_opv system call
Message-ID: <20171120184927.GK2482@two.firstfloor.org>
References: <20171114200414.2188-1-mathieu.desnoyers@efficios.com>
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> Having cpu_opv do a 4k memcpy allow it to handle scenarios where
> rseq fails to progress.

If anybody ever gets that right. It will be really hard to just
test such a path.

It also seems fairly theoretical to me. Do you even have a 
test case where the normal path stops making forward progress?

-Andi