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Date:   Wed, 10 Mar 2021 20:08:10 +0100
From:   Piotr Figiel <figiel@google.com>
To:     Alexey Dobriyan <adobriyan@gmail.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Kees Cook <keescook@chromium.org>,
        Alexey Gladkov <gladkov.alexey@gmail.com>,
        Michel Lespinasse <walken@google.com>,
        Bernd Edlinger <bernd.edlinger@hotmail.de>,
        Andrei Vagin <avagin@gmail.com>,
        mathieu.desnoyers@efficios.com, viro@zeniv.linux.org.uk,
        peterz@infradead.org, paulmck@kernel.org, boqun.feng@gmail.com
Cc:     linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        posk@google.com, kyurtsever@google.com, ckennelly@google.com,
        pjt@google.com
Subject: Re: [PATCH v4] fs/proc: Expose RSEQ configuration
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References: <20210202173709.4104221-1-figiel@google.com>
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On Tue, Feb 02, 2021 at 06:37:09PM +0100, Piotr Figiel wrote:
> For userspace checkpoint and restore (C/R) some way of getting process
> state containing RSEQ configuration is needed.

[...]

> To achieve above goals expose the RSEQ ABI address and the signature
> value with the new procfs file "/proc/<pid>/rseq".

For the record: this idea was dropped in favor of ptrace approach, as
discussed over separate mail thread with Mathieu Desnoyers and Peter
Zijlstra.  The equivalent ptrace patch in its current version is here:

https://lore.kernel.org/lkml/20210226135156.1081606-1-figiel@google.com/

Best regards,
Piotr.