RFC: fb restore on drm master close

[vcaputo at pengaru.com]

Hello list,

I've been playing with an unaccelerated drm program[1] and have been
annoyed that whenever this program exits the fbcon isn't restored, with
the display left completely off.

This seems to happen because Xorg is still running from a different VT.

Upon further investigation, it seems like the fb restore only occurs on
"lastclose", which explains what I'm observing.

Why don't we perform the fb restore whenever the current master is
closed to cover this case, since masters are the ones that can change
modes?

My github has a quick-n-dirty i915 implementation[2] which seems to fix
this without negative effects, though I haven't exhaustively tested to
see what breaks.

This isn't a list I subscribe to so please CC me directly in any
replies, thanks everyone!

Regards,
Vito Caputo


1. https://github.com/vcaputo/rototiller
2. https://github.com/torvalds/linux/compare/master...vcaputo:masterclose?expand=1