Set the "untrusted" attribute to any PCIe port that has an
"external-facing" device tree property. Any device downstream of this
port will inherit the attribute and have only the strictest IOMMU
protection.
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@xxxxxxx>
---
v2->v3:
* Use of_property_read_bool().
* Firmware can in theory set the property on the host bridge node.
Handle this case.
* Don't pass a NULL node to the of driver. Although it is handled
gracefully at the moment, it isn't documented and we might as well
proof this too.
---
drivers/pci/of.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)
diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index 3d32da15c215..67376cf45880 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -31,10 +31,16 @@ void pci_release_of_node(struct pci_dev *dev)
void pci_set_bus_of_node(struct pci_bus *bus)
{
- if (bus->self == NULL)
- bus->dev.of_node = pcibios_get_phb_of_node(bus);
- else
- bus->dev.of_node = of_node_get(bus->self->dev.of_node);
+ struct device_node *node;
+
+ if (bus->self == NULL) {
+ node = pcibios_get_phb_of_node(bus);
+ } else {
+ node = of_node_get(bus->self->dev.of_node);
+ if (node && of_property_read_bool(node, "external-facing"))
+ bus->self->untrusted = true;
+ }
+ bus->dev.of_node = node;
}
void pci_release_bus_of_node(struct pci_bus *bus)
--
2.21.0
