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Date:   Mon, 30 Mar 2020 17:49:44 -0700 (PDT)
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To:     stefano.salsano@uniroma2.it
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Subject: Re: [net-next] seg6: add support for optional attributes during
 behavior construction
From:   David Miller <davem@davemloft.net>
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        <20200325.193016.1654692564933635575.davem@davemloft.net>
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From: Stefano Salsano <stefano.salsano@uniroma2.it>
Date: Tue, 31 Mar 2020 01:23:48 +0200

> Of course a new application (e.g. iproute2, pyroute) using a new optional
> parameter will not work on older kernels, but simply because the new parameter
> is not supported. It will not work even without our proposed patch.
> 
> On the other hand, we think that the solution in the patch is more backward
> compatible. Without the patch, if we define new attributes, old applications
> (e.g. iproute2 scripts) will not work on newer kernels, while with the optional
> attributes approach proposed in the patch they will work with no issues !

Translation: You want to add backwards compatibility problems because
otherwise you'll have to add backwards compatibility problems.

Sorry, I'm still not convinced.

You must find another way to achieve your objective.