Comment 37 for bug 840140

If you are getting rendering errors, it's possible the cursor image was rendered as garbage. Can you try this patch in addition to the backend_map changes?

diff --git a/drivers/gpu/drm/radeon/evergreen.c b/drivers/gpu/drm/radeon/evergreen.c
index 3e8054c..4d66a05 100644
--- a/drivers/gpu/drm/radeon/evergreen.c
+++ b/drivers/gpu/drm/radeon/evergreen.c
@@ -1832,7 +1832,7 @@ static void evergreen_gpu_init(struct radeon_device *rdev)
                rdev->config.evergreen.sc_earlyz_tile_fifo_size = 0x130;
                break;
        case CHIP_BARTS:
- rdev->config.evergreen.num_ses = 2;
+ rdev->config.evergreen.num_ses = 1;
                rdev->config.evergreen.max_pipes = 4;
                rdev->config.evergreen.max_tile_pipes = 8;
                rdev->config.evergreen.max_simds = 7;