To be honest you weren't the first to come up with something like this
(although you're the first to post to l-k as far as I know). But the
usual problem of something that is kept out of tree is that it
eventually bitrots and gets forgotten. The only sane way to make such
extensions a generically usable linux feature is to merge them to mainline.
(2) is a incredibly large amount of work longer time. And when
distributions merge your feature they become committed to it so even if
you go away they would still need to maintain it on their own. Since
they understand how much work this is they likely won't do it in the
first place. Really it's far better to just merge if you want it to
make it out of the "toy" stage.
-Andi
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