1 files changed, 41 insertions, 13 deletions

diff --git a/sys/dev/iommu/busdma_iommu.c b/sys/dev/iommu/busdma_iommu.c
index 6856b0551dde..668ccf056463 100644
--- a/sys/dev/iommu/busdma_iommu.c
+++ b/sys/dev/iommu/busdma_iommu.c
@@ -114,8 +114,8 @@ iommu_bus_dma_is_dev_disabled(int domain, int bus, int slot, int func)
  * domain, and must collectively be assigned to use either IOMMU or
  * bounce mapping.
  */
-device_t
-iommu_get_requester(device_t dev, uint16_t *rid)
+int
+iommu_get_requester(device_t dev, device_t *requesterp, uint16_t *rid)
 {
 	devclass_t pci_class;
 	device_t l, pci, pcib, pcip, pcibp, requester;
@@ -129,7 +129,8 @@ iommu_get_requester(device_t dev, uint16_t *rid)
 	pci = device_get_parent(dev);
 	if (pci == NULL || device_get_devclass(pci) != pci_class) {
 		*rid = 0;	/* XXXKIB: Could be ACPI HID */
-		return (requester);
+		*requesterp = NULL;
+		return (ENOTTY);
 	}
 
 	*rid = pci_get_rid(dev);
@@ -141,16 +142,39 @@ iommu_get_requester(device_t dev, uint16_t *rid)
 	 */
 	for (;;) {
 		pci = device_get_parent(l);
-		KASSERT(pci != NULL, ("iommu_get_requester(%s): NULL parent "
-		    "for %s", device_get_name(dev), device_get_name(l)));
-		KASSERT(device_get_devclass(pci) == pci_class,
-		    ("iommu_get_requester(%s): non-pci parent %s for %s",
-		    device_get_name(dev), device_get_name(pci),
-		    device_get_name(l)));
+		if (pci == NULL) {
+			if (bootverbose) {
+				printf(
+			"iommu_get_requester(%s): NULL parent for %s\n",
+				    device_get_name(dev), device_get_name(l));
+			}
+			*rid = 0;
+			*requesterp = NULL;
+			return (ENXIO);
+		}
+		if (device_get_devclass(pci) != pci_class) {
+			if (bootverbose) {
+				printf(
+			"iommu_get_requester(%s): non-pci parent %s for %s\n",
+				    device_get_name(dev), device_get_name(pci),
+				    device_get_name(l));
+			}
+			*rid = 0;
+			*requesterp = NULL;
+			return (ENXIO);
+		}
 
 		pcib = device_get_parent(pci);
-		KASSERT(pcib != NULL, ("iommu_get_requester(%s): NULL bridge "
-		    "for %s", device_get_name(dev), device_get_name(pci)));
+		if (pcib == NULL) {
+			if (bootverbose) {
+				printf(
+			"iommu_get_requester(%s): NULL bridge for %s\n",
+				    device_get_name(dev), device_get_name(pci));
+			}
+			*rid = 0;
+			*requesterp = NULL;
+			return (ENXIO);
+		}
 
 		/*
 		 * The parent of our "bridge" isn't another PCI bus,
@@ -229,7 +253,8 @@ iommu_get_requester(device_t dev, uint16_t *rid)
 			}
 		}
 	}
-	return (requester);
+	*requesterp = requester;
+	return (0);
 }
 
 struct iommu_ctx *
@@ -237,10 +262,13 @@ iommu_instantiate_ctx(struct iommu_unit *unit, device_t dev, bool rmrr)
 {
 	device_t requester;
 	struct iommu_ctx *ctx;
+	int error;
 	bool disabled;
 	uint16_t rid;
 
-	requester = iommu_get_requester(dev, &rid);
+	error = iommu_get_requester(dev, &requester, &rid);
+	if (error != 0)
+		return (NULL);
 
 	/*
 	 * If the user requested the IOMMU disabled for the device, we