[Linux-fbdev-devel] Re: Who is stomping PCI config space?

[Jon Smirl]

In the past Jesse Barnes has suggested a completely different approach
to VGA sharing. Instead of each VT trying to control which VGA device
is enabled we keep them all turned off. Then on each access we turn
VGA support on just long enough for the access and then turn it back
off.

To make this work we have to have a kernel based 'token' for who has
the VGA at the moment. This scheme lets multiuser systems work. For
big IA64 machines which can support multiple simultaneous VGAs we just
have multiple tokens.

We would just ban VGA access from interrupt context, if you really
needed VGA access you would use a workqueue which can be scheduled
from the interrupt. None of my driver work needs VGA access from
interrupt context, is this true for all drivers? I need access to the
video hardware, but not access to the VGA support.

-- 
Jon Smirl
jonsmirl at gmail.com