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Message-ID: <5423CA53.5020207@6wind.com>
Date: Thu, 25 Sep 2014 09:54:59 +0200
From: Nicolas Dichtel <nicolas.dichtel@6wind.com>
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To: Andy Lutomirski <luto@amacapital.net>
CC: Network Development <netdev@vger.kernel.org>,
        Linux Containers <containers@lists.linux-foundation.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Linux API <linux-api@vger.kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Stephen Hemminger <stephen@networkplumber.org>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [RFC PATCH net-next v2 0/5] netns: allow to identify peer netns
References: <1411478430-4989-1-git-send-email-nicolas.dichtel@6wind.com> <CALCETrWnZtWstBviDxcHpLpjHF3R+sgS48RYf2pbKBYeExZVOQ@mail.gmail.com> <54228F8B.2030804@6wind.com> <CALCETrXMkV_1XR2mXOoO_2_vpB=6cPbWAAOhPFhPbDa_1P+zxw@mail.gmail.com>
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Le 24/09/2014 19:05, Andy Lutomirski a écrit :
> On Wed, Sep 24, 2014 at 2:31 AM, Nicolas Dichtel
> <nicolas.dichtel@6wind.com> wrote:
>> Le 23/09/2014 21:26, Andy Lutomirski a écrit :
>>
>>> On Tue, Sep 23, 2014 at 6:20 AM, Nicolas Dichtel
>>> <nicolas.dichtel@6wind.com> wrote:
>>>>
>>>> The goal of this serie is to be able to multicast netlink messages with
>>>> an
>>>> attribute that identify a peer netns.
>>>> This is needed by the userland to interpret some informations contained
>>>> in
>>>> netlink messages (like IFLA_LINK value, but also some other attributes in
>>>> case
>>>> of x-netns netdevice (see also
>>>> http://thread.gmane.org/gmane.linux.network/315933/focus=316064 and
>>>> http://thread.gmane.org/gmane.linux.kernel.containers/28301/focus=4239)).
>>>>
>>>> Ids are stored in the parent user namespace. These ids are valid only
>>>> inside
>>>> this user namespace. The user can retrieve these ids via a new netlink
>>>> messages,
>>>> but only if peer netns are in the same user namespace.
>>>
>>>
>>> What about the parent / ancestors of the owning userns?  Can processes
>>> in those usernses see any form of netns id?
>>
>> With this serie no. I'm not sure if ancestors really needs to be able to
>> get these ids. What is your opinion?
>
> I might be missing some consideration here, but I would hope that ip
> link would work correctly if I have a veth interface shared with a
> netns that's in a child userns.
No, you're right. Will send a v3.