Comment # 10 on bug 73297 from Anton Sudak

I belive that this two bugs are related and possibly bug 74211 is duplicate. If
you look at logs you can see that there are same traces (search for
drm_mm_takedown+0x2f/0x40). I can be wrong, but I think that the same problem
occurs in different time.

In this bug radeon module crashes when xorg tries to use it and this cause Xorg
to crash too. I closed this bug mistakenly, I added radeon.runpm=1 flag and
forgot about this. This flag cause radeon module to crash before Xorg start so
I thinked that my bug was resolved.
In bug 74211 I runned kernel with radeon.runpm=1 and radeon module crashes
before Xorg start, so X finds only one working module - i915 and that's why it
starts normally and I don't see my Radeon videocard.