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Date: Wed, 6 Apr 2016 21:25:34 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Paul Turner <commonly@gmail.com>, Andrew Hunter <ahh@google.com>,
        Andy Lutomirski <luto@amacapital.net>,
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        linux-api <linux-api@vger.kernel.org>, linux-kernel@vger.kernel.org,
        Josh Triplett <josh@joshtriplett.org>, Ingo Molnar <mingo@redhat.com>,
        Chris Lameter <cl@linux.com>,
        Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [RFC PATCH v2 3/3] restartable sequences: basic self-tests
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On Wed, Apr 06, 2016 at 01:39:22PM +0000, Mathieu Desnoyers wrote:
> There is still the question of use-after-free however that
> remains open. My understanding is that this lock-free list
> should be paired with either a type-safe memory allocator,
> using RCU, or a garbage collector.

Yeah, it looks that way indeed, there no sane way to fix that either,
even if you stick all this inside the rseq_start/finish thing you'll get
use-after-free, because we'll not restart until rseq_finish fails.