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Date: Thu, 1 Sep 2016 16:59:20 +0300
From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>,
        Dmitry Safonov <dsafonov@virtuozzo.com>, linux-kernel@vger.kernel.org,
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        Ingo Molnar <mingo@redhat.com>, linux-mm@kvack.org,
        X86 ML <x86@kernel.org>, Pavel Emelyanov <xemul@virtuozzo.com>
Subject: Re: [PATCHv4 6/6] x86/signal: add SA_{X32,IA32}_ABI sa_flags
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On Thu, Sep 01, 2016 at 04:47:23PM +0300, Dmitry Safonov wrote:
> Thanks for your replies Oleg, Cyrill,
> 
> 2016-09-01 15:45 GMT+03:00 Cyrill Gorcunov <gorcunov@gmail.com>:
> > On Thu, Sep 01, 2016 at 02:27:44PM +0200, Oleg Nesterov wrote:
> >> > Hi Oleg,
> >> > can I have your acks or reviewed-by tags for 4-5-6 patches in the series,
> >> > or there is something left to fix?
> >>
> >> Well yes... Although let me repeat, I am not sure I personally like
> >> the very idea of 3/6 and 6/6. But as I already said I do not feel I
> >> understand the problem space enough, so I won't argue.
> >>
> >> However, let me ask again. Did you consider another option? Why criu
> >> can't exec a dummy 32-bit binary before anything else?
> >
> > I'm not really sure how this would look then. If I understand you
> > correctly you propose to exec dummy 32bit during "forking" stage
> > where we're recreating a process tree, before anything else. If
> > true this implies that we will need two criu engines: one compiled
> > with 64 bit and (same) second but compiled with 32 bits, no?
> 
> Yep, we would need then full CRIU, but compiled in 32 bits.
> And it can be then even more complicated, as 64-bit parent
> can have 32-bit child, which can have 64-bit child... et cetera.

Yup, this gonna be a mess, that's why I asked, because I suspect
Oleg meant something else maybe?