2.6.0-test9-ruby: console switch on VT0 disrupts XFree86 on VT1

[Wayne W. <wh...@Ma...>]

Hello,

I'm very happy to have gotten my dual user setup running under ruby, I'm
quite impressed with it.  I am still having one problem, though, which was
also present in my Miguel Freitas style setup.  When I switch from X to
VGA console on VT0 (from vt7 to vt1, say), or if I just log out of X on
VT0, it disrupts the X display on VT1 (vt17).  That is, the DFP on VT1
reports that its input is out of range.

Details:  VT0 is running on an AGP Radeon VE QY and VT1 is running on a
PCI Radeon VE QY; the kernel is 2.6.0-test9-ruby, with the keyboard.c
change as in CVS and the vt_ioctl.c change as in my previous email; X is
XFree86 4.3.99.15 with the PrefBusID patch (version 3), which is enabled;
I'm running gdm from Fedora Core 1.

Any ideas on how to avoid this?  I've tried enabling DEBUG in XFree86's
xf86pciBus.c, to see if logging out of X on VT0 led to some PCI accesses,
but the only PCI access debug statements that were logged occurred at the
startup of X.  Is there an easy way for me to dump the state of the PCI
Radeon both before and after the console switch/X logout?

One workaround I've thought of is this:  X already has the code needed to
restore its display after console switch, so if I had a simple way to
initiate a fake console switch for X on VT1, it should restore the
display.  Any suggestions on how to do this?

Any help would be very appreciated.  I also included below a few minor
questions I have.

Thanks,
Wayne

1) Why does section 4.3 of the HOWTO suggest using a different symlink for
each instance of X?  Things seem to work for me without this, and I
checked that this doesn't fix my problem.

2) Also, I don't seem to have any trouble with gpm.  I have it setup to
use /dev/psaux, and my X instances are using /dev/input/miceX.  My gpm RPM
is gpm-1.20.1-38.

3) If I understand correctly, the legacy VGA area is only routed to one
video card at a time.  If the X on VT1 reroutes the legacy VGA area from
the VT0 AGP card to the VT1 PCI card, behind the back of the already
running X on VT0, won't this cause problems?  How does the kernel VT
system handles the legacy VGA area routing?