diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index 66665c82415cc7810a0e42787bd8d93a198e31bb..eec684a8e44e1bc7176df1f29120631d1b8f5474 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -504,6 +504,12 @@ static void pci_dma_dev_setup_pSeriesLP(struct pci_dev *dev)
 			break;
 	}
 
+	if (!pdn || !PCI_DN(pdn)) {
+		printk(KERN_WARNING "pci_dma_dev_setup_pSeriesLP: "
+		       "no DMA window found for pci dev=%s dn=%s\n",
+				 pci_name(dev), dn? dn->full_name : "<null>");
+		return;
+	}
 	DBG("  parent is %s\n", pdn->full_name);
 
 	/* Check for parent == NULL so we don't try to setup the empty EADS