Re: [PATCH] drm/i915: revert vga arbiter changes

On Tue, Oct 08, 2013 at 05:27:28PM +0200, Daniel Vetter wrote:

Adding drm/i915 into the vga arbiter chain means that X (in a piece of well-meant paranoia) will do a get/put on the vga decoding around _every_ accel call down into the ddx. Which results in some nice performance disasters [1].

And disables DRI for the system, interferring with the use of OpenGL compositors, playing games, PRIME, etc. This effect is not limited to users of i915, but any system with a dGPU and an igfx enabled Core CPU.

I still think we are downplaying the complete and utter disaster caused by X and the patch, and why the revert is required. -Chris