SRU Justification:

Impact: After dropping a sauce patch to make vesafb a module we
accidentally dropped a change to make mtrr:3 (write-combining remap
range) the default. This results in a performance degradation for
graphics cards that have no drm framebuffer driver (especially on higher
resolutions).

Fix: Change default for mtrr setting from none to 3 (write-combining).

Testcase: With any hardware that ends up having vesafb (VESA VGA) as
framebuffer device performance is slower and the mapped address will not
show up in /proc/mtrr. After changing the default /proc/mtrr should show
a write-combining entry and performance should be improved.

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https://bugs.launchpad.net/bugs/1434581

Title:
  Console extremely slow with 3.13 and newer kernels for certified
  servers with Matrox G200er2 or similar

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