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Date: Wed, 2 Nov 2016 19:18:06 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Jann Horn <jann@thejh.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>,
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Subject: Re: [PATCH v3 1/8] exec: introduce cred_guard_light
Message-ID: <20161102181806.GB1112@redhat.com>
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On 10/30, Jann Horn wrote:
>
> This is a new per-threadgroup lock that can often be taken instead of
> cred_guard_mutex and has less deadlock potential. I'm doing this because
> Oleg Nesterov mentioned the potential for deadlocks, in particular if a
> debugged task is stuck in execve, trying to get rid of a ptrace-stopped
> thread, and the debugger attempts to inspect procfs files of the debugged
> task.

Yes, but let me repeat that we need to fix this anyway. So I don't really
understand why should we add yet another mutex.

Oleg.