From: Stefano Salsano <stefano.salsano@xxxxxxxxxxx> 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.