** Description changed:

  In its current form, X fails to match Geode LX hardware with the
  corresponding "geode" X driver, instead reverting to the "vesa" driver,
  on hosts launching without any xorg.conf, or whose xorg.conf omits the
  Driver statement in the Device section.
  
  This has been verified on various Geode LX -based hardware featuring
  BIOS from a variety of vendors.
  
  Suspicion is that patching hw/xfree86/common/xf86AutoConfig.c to add the
  PCI ID for Geode LX would fix this. A patch is attached towards this
  effect.
+ 
+ ---
+ 
+ 
+ 1. Impact:  The bug is a failure to match the graphics hardware that is built 
into Geode chipset with the corresponding X driver.
+ 
+ a) On desktop hosts, the result is that running X without any xorg.conf
+ or with an xorg.conf that omits the driver name will have X revert to
+ the VESA driver. This produces sub-optimal performance and an unability
+ to use chipset-specific features that are present in the "geode" driver.
+ 
+ b) On LTSP hosts, which uses a different method for configuring X, this
+ fails for a completely different reason, because X core follows a
+ different method for producing an xorg.conf using "Xorg -configure" than
+ for configuration-less chipset matching.
+ 
+ 2. How it's addressed:
+ a) The desktop case is fixed with the enclosed patch, by adding the PCI ID 
for the Geode LX to hw/xfree86/common/xf86AutoConfig.c.
+ b) Fixing the LTSP case will require further investigation.
+ 
+ 3. The patch for the desktop case is attached to this bug.
+ 
+ 4. To reproduce this issue, launch X (e.g. using "startx") from console,
+ on a Geode LX -based desktop host without any xorg.conf present. Then,
+ examining the X log, we notice that the VESA driver was used by X. After
+ the patch has been applied, repeating the test produces an X log that
+ correctly shows that X used the "geode" X driver.
+ 
+ 5. The patch cannot introduce any regression. Rather, it introduces
+ positive PCI ID matching in a situation where it was not existent.

-- 
X fails to use GEODE and reverts to VESA on a host without any xorg.conf
https://bugs.launchpad.net/bugs/220510
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