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Date: Thu, 24 May 2018 09:28:27 -0600
From: Tycho Andersen <tycho@tycho.ws>
To: Oleg Nesterov <oleg@redhat.com>
Cc: linux-kernel@vger.kernel.org, containers@lists.linux-foundation.org,
        Kees Cook <keescook@chromium.org>,
        Andy Lutomirski <luto@amacapital.net>,
        "Eric W . Biederman" <ebiederm@xmission.com>,
        "Serge E . Hallyn" <serge@hallyn.com>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Tyler Hicks <tyhicks@canonical.com>,
        Akihiro Suda <suda.akihiro@lab.ntt.co.jp>,
        "Tobin C . Harding" <me@tobin.cc>
Subject: Re: [PATCH v2 1/4] seccomp: add a return code to trap to userspace
Message-ID: <20180524152827.GD21405@cisco>
References: <20180517151218.12850-1-tycho@tycho.ws>
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 <20180517153323.GA8586@redhat.com>
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Hi Oleg,

On Thu, May 17, 2018 at 05:46:37PM +0200, Oleg Nesterov wrote:
> On 05/17, Tycho Andersen wrote:
> >
> > > From lockdep pov this loop tries to take the same lock twice or more, it shoul
> > > complain.
> >
> > I didn't, but I guess that's because it's not trying to take the same lock
> > twice -- the pointer cur is changing in the loop.
> 
> Yes, I see. But this is the same lock for lockdep, it has the same class.

I finally figured this out, I needed CONFIG_PROVE_LOCKING=y too,
anyway, I've added the nesting annotations for v3. Thanks!

Tycho