netdev - Re: [PATCH net-next] vxlan: don't bypass encapsulation for multi- and broadcasts

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Date:	Mon, 15 Apr 2013 16:32:57 +0300
From:	Mike Rapoport <mike.rapoport@...ellosystems.com>
To:	David Miller <davem@...emloft.net>
Cc:	netdev@...r.kernel.org, stephen@...workplumber.org
Subject: Re: [PATCH net-next] vxlan: don't bypass encapsulation for multi- and broadcasts

On Mon, Apr 15, 2013 at 8:45 AM, David Miller <davem@...emloft.net> wrote:
> From: Mike Rapoport <mike.rapoport@...ellosystems.com>
> Date: Mon, 15 Apr 2013 08:31:15 +0300
>
>> On Sun, Apr 14, 2013 at 10:39 PM, David Miller <davem@...emloft.net> wrote:
>>> From: Mike Rapoport <mike.rapoport@...ellosystems.com>
>>> Date: Sun, 14 Apr 2013 12:21:51 +0300
>>>
>>>> The multicast and broadcast packets may have RTCF_LOCAL set in rt_flags
>>>> and therefore will be sent out bypassing encapsulation. This breaks
>>>> delivery of packets sent to the vxlan multicast group.
>>>> Disabling encapsulation bypass for multicasts and broadcasts fixes the
>>>> issue.
>>>>
>>>> Signed-off-by: Mike Rapoport <mike.rapoport@...ellosystems.com>
>>>
>>> This still won't handle the case of encapsulations occuring in different
>>> namespaces or virtual machines.
>>>
>>> I really want this fixed correctly.
>>
>> I'm sorry, but I don't quite follow you. The patch does not aim to
>> reduce the amount of encapsulation. On the contrary, it prevents some
>> packets from being encapsulated when they should not be...
>
> I'm saying you need to make sure the bypass is avoided in these
> situations as well.

I've tried the cases with different namespaces and virtual machines.
Both worked for me.
Maybe I'm missing something, but I could not identify a case where
encapsulation occurs when it should not.

> There is an ongoing discussion about this on the list between Cong
> Wang and the author of the bypass changes.

And it seems that for Sridhar Samudrala it worked as well :)

-- 
Sincerely yours,
Mike.
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