Bug#508476: FatalError with no config and fbdev..

[Julien Cristau <jcristau@debian.org>]

Hi,

so I finally sat down yesterday to take a look at this.  Here's what
happens as far as I can tell:
- the intel (or whatever) driver gets loaded, its PciProbe hook is
  called by probe_devices_from_device_sections(), and it claims the pci
  device
- then fbdev gets loaded.  Since the device is already claimed,
  xf86CheckPciSlot() in probe_devices_from_device_sections() returns 0,
  so xf86CallDriverProbe() calls the Probe hook instead of PciProbe.
  When there's no BusId, and /dev/fb0 exists, fbdev's Probe hook calls
  xf86ClaimFbSlot()
- finally, in xf86PostProbe() both fbSlotClaimed and pciSlotClaimed are
  true, so we FatalError()

I'm not sure when this started happening (I'd guess pci-rework, but I'm
not sure since I never had a framebuffer device before playing with
this, and I always had an xorg.conf), or how to fix it...

Cheers,
Julien