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Date: Wed, 21 Jun 2017 19:31:15 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>, Hugh Dickins <hughd@google.com>,
        Andrey Vagin <avagin@openvz.org>, LKML <linux-kernel@vger.kernel.org>,
        Pavel Emelyanov <xemul@virtuozzo.com>,
        Andrew Morton <akpm@linuxfoundation.org>,
        Adrian Reber <areber@redhat.com>
Subject: Re: [criu] 1M guard page ruined restore
Message-ID: <20170621173115.GA28723@redhat.com>
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On 06/21, Dmitry Safonov wrote:
>
> The only question I have - how is it connected to guard page?

Because with stack guard page do_page_fault() almost never needs to
call expand_stack(), thus this check was almost never tested, I guess.
Probably it should go away now.

I'll write the changelog and patch tomorrow, unless someone does this
before.

Oleg.