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Date:   Mon, 15 Mar 2021 16:52:35 +0300
From:   Cyrill Gorcunov <gorcunov@gmail.com>
To:     Oleg Nesterov <oleg@redhat.com>
Cc:     Alexey Dobriyan <adobriyan@gmail.com>, akpm@linux-foundation.org,
        linux-kernel@vger.kernel.org, security@kernel.org
Subject: Re: [PATCH] prctl: fix PR_SET_MM_AUXV kernel stack leak
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On Mon, Mar 15, 2021 at 02:19:12PM +0100, Oleg Nesterov wrote:
> > >
> > > And why task_lock(current) ? What does it try to protect?
> >
> > As far as I remember this was related to reading from procfs
> > at time the patch was written for first time. Looks like this
> > not relevant anymore and could be dropped.
> 
> I think this was never relevant, ->alloc_lock is per-thread, not per mm.

Then we can safely drop it. I'll take one more look once time permit
and prepare a patch.