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Message-ID: <1538396819.4348.86.camel@arista.com>
Subject: Re: [RFC 0/2] ns: introduce binfmt_misc namespace
From: Dmitry Safonov <dima@arista.com>
To: Laurent Vivier <laurent@vivier.eu>,
        Andy Lutomirski <luto@kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Linux FS Devel <linux-fsdevel@vger.kernel.org>,
        James Bottomley <James.Bottomley@hansenpartnership.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Linux API <linux-api@vger.kernel.org>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Andrey Vagin <avagin@openvz.org>,
        Linux Containers <containers@lists.linux-foundation.org>
Date: Mon, 01 Oct 2018 13:26:59 +0100
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References: <20180930234628.25528-1-laurent@vivier.eu>
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         <d1b6b52b-dd7f-fa27-eafa-7a6a43a03b92@vivier.eu>
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Hi Laurent, thanks for Cc,

On Mon, 2018-10-01 at 09:13 +0200, Laurent Vivier wrote:
> Le 01/10/2018 à 06:45, Andy Lutomirski a écrit :
> > On Sun, Sep 30, 2018 at 4:47 PM Laurent Vivier <laurent@vivier.eu>
> > wrote:
> > > 
> > > This series introduces a new namespace for binfmt_misc.
> > > 
> > 
> > This seems conceptually quite reasonable, but I'm wondering if the
> > number of namespace types is getting out of hand given the current
> > API.  Should we be considering whether we need a new set of
> > namespace
> > creation APIs that scale better to larger numbers of namespace
> > types?
> > 
> 
> Yes, we need something to increase the maximum number of namespace
> types
> because this is the last bit in the clone() flags and the time
> namespace
> has already preempted it.

Yeah, there is this last CLONE_* flag..
I tried to use that 0x1000 flag for something like CLONE_EXTENDED with
all parameters on the stack, but not sure that's reasonable and maybe
someone will suggest a better solution.
All those different clone() ABI (how many parameters to supply and in
which order do not help much).

-- 
Thanks,
             Dmitry