[systemd-devel] The meaning of CanMultiSession=no on non-seat0

[Lennart Poettering]

On Fr, 03.04.20 10:28, Pekka Paalanen (ppaalanen at gmail.com) wrote:

> > My (maybe bad) guess is that it would need to be addressed in the kernel though
> > And the CanMultiSession attribute on non-seat0 doesn't matter when the problem
> > is all input from all devices gets sent to seat0 when seat0 is in a text mode
> > TTY
> >
> > ..and even if you have some kmscon like thing installed, there could still be
> > text mode TTYs
>
> Hi,
>
> that is both an excellent and horrifying observation. And it makes
> perfect sense to me why that happens, just like you think: seat
> assignments happen in userspace as udev properties. Someone would have
> to explicitly tell the kernel about it too to fix this, e.g. remove
> non-seat0 devices from the VT machinery.
>
> I wonder if such kernel interface even exists?

There are ioctls for that in the input layer if iirc, but i don't
remember how precisely this works. You are hacking on a compositor, you
should know ;-)

Lennart

--
Lennart Poettering, Berlin