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Date: Mon, 21 Dec 2009 18:02:37 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Andi Kleen <andi@firstfloor.org>
Cc: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
       Roland McGrath <roland@redhat.com>
Subject: Re: BKL use in ptrace
Message-ID: <20091221170237.GA5384@redhat.com>
References: <20091220185318.GA15989@basil.fritz.box>
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(add Roland)

On 12/20, Andi Kleen wrote:
>
> ptrace has this comment/BKL use:
>
>         /*
>          * This lock_kernel fixes a subtle race with suid exec
>          */
>         lock_kernel();
>
> But unless I'm blind I don't see execve actually getting the BKL
> anywhere. So is this comment outdated or misleading (is the race with exit?)
> or is there a bug?

I never understood this lock_kernel().

In any case it looks outdated. We were going to kill it "soon",
along with other ptrace changes.

Oleg.