--- ./drivers/passthrough/vtd/iommu.c.bak	2016-01-24 12:55:15.020267553 -0500
+++ ./drivers/passthrough/vtd/iommu.c	2016-01-24 12:57:14.754138262 -0500
@@ -717,6 +717,7 @@
         {
             dprintk(XENLOG_WARNING VTDPREFIX,
                     "BIOS did not enable IGD for VT properly.  Disabling IGD VT-d engine.\n");
+            disable_pmr(iommu);
             return;
         }
     }