the reason is pretty simple; the a kernel driver should not do any
kind of policy, namespace or whatever you wanna call it. This should
be done in userspace.
And some operating system really suffer from this ABI guarantee. I am
not getting into this since it has been discussed so many times and
the kernel source contains full documentation why we are not doing it.
We actually do and we the future remove document and the requirements
document within the kernel source this is fully documented all of the
time.
However you have to understand that at some point we have to make sure
that kernel and userspace are recent. But again, this will be all
documented and if a distro than decides to bluntly ignore it, then go
ahead an blame the distro. The kernel depends on the "plumbing" and
vise versa.
Regards
Marcel
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