diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 8bea336fa5b7..b858f186e9a7 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -172,17 +172,28 @@ static int fail_iommu_bus_notify(struct notifier_block *nb,
 	return 0;
 }
 
-static struct notifier_block fail_iommu_bus_notifier = {
+/*
+ * PCI and VIO buses need separate notifier_block structs, since they're linked
+ * list nodes.  Sharing a notifier_block would mean that any notifiers later
+ * registered for PCI buses would also get called by VIO buses and vice versa.
+ */
+static struct notifier_block fail_iommu_pci_bus_notifier = {
 	.notifier_call = fail_iommu_bus_notify
 };
 
+#ifdef CONFIG_IBMVIO
+static struct notifier_block fail_iommu_vio_bus_notifier = {
+	.notifier_call = fail_iommu_bus_notify
+};
+#endif
+
 static int __init fail_iommu_setup(void)
 {
 #ifdef CONFIG_PCI
-	bus_register_notifier(&pci_bus_type, &fail_iommu_bus_notifier);
+	bus_register_notifier(&pci_bus_type, &fail_iommu_pci_bus_notifier);
 #endif
 #ifdef CONFIG_IBMVIO
-	bus_register_notifier(&vio_bus_type, &fail_iommu_bus_notifier);
+	bus_register_notifier(&vio_bus_type, &fail_iommu_vio_bus_notifier);
 #endif
 
 	return 0;