--- shared-core/i915_dma.c	2007-01-09 13:52:19.000000000 +0800
+++ shared-core/i915_dma.c.new	2007-01-09 14:02:32.000000000 +0800
@@ -63,6 +63,7 @@
 			i = 0;
 
 		last_head = ring->head;
+		DRM_UDELAY(1);
 	}
 
 	return DRM_ERR(EBUSY);