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Date: Wed, 18 Apr 2018 12:02:17 +0300
From: Cyrill Gorcunov <gorcunov@gmail.com>
Subject: Re: [v4 PATCH] mm: introduce arg_lock to protect arg_start|end and
 env_start|end in mm_struct
Message-ID: <20180418090217.GG19578@uranus.lan>
References: <1523730291-109696-1-git-send-email-yang.shi@linux.alibaba.com>
 <20180418080555.GR17484@dhcp22.suse.cz>
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To: Michal Hocko <mhocko@kernel.org>
Cc: Yang Shi <yang.shi@linux.alibaba.com>, adobriyan@gmail.com, willy@infradead.org, mguzik@redhat.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org

On Wed, Apr 18, 2018 at 10:05:55AM +0200, Michal Hocko wrote:
> 
> Yes, looks good to me. As mentioned in other emails prctl_set_mm_map
> really deserves a comment explaining why we are doing the down_read
> 
> What about something like the following?
> "
> arg_lock protects concurent updates but we still need mmap_sem for read
> to exclude races with do_brk.
> "
> Acked-by: Michal Hocko <mhocko@suse.com>

Yes, thanks! Andrew, could you slightly update the changelog please?