--- a/backport-include/linux/dma-mapping.h
+++ b/backport-include/linux/dma-mapping.h
@@ -15,7 +15,7 @@
 }
 #endif
 
-#if LINUX_VERSION_CODE < KERNEL_VERSION(3,13,0)
+#if 0
 /*
  * Set both the DMA mask and the coherent DMA mask to the same thing.
  * Note that we don't check the return value from dma_set_coherent_mask()