Re: [Linux-fbdev-devel] Some questions

[Antonino D. <ad...@po...>]

On Wed, 2003-03-12 at 06:23, Thomas Winischhofer wrote:
> > 
> > I actually prefer #3, and I already have working code for this.  We can
> > also make this driver switchable (ie, drivers that are not affected by X
> > can disable this, and only drivers that are affected such as the riva,
> > aty, radeon, etc can turn this on).
> 
> What exactly is a "trusted" console?
> 

By default, the pid of each vt is -1.  When X loads, it installs its own
VT (ie vt7), which in that case the pid of that particular vt == X's
pid.  We can check this pid, and if switching from a vt with pid == -1,
we can safely assume that the hardware state is still sane, and if not,
assume the hardware state is undefined.

Tony