"External-facing" devices are internal devices that expose PCIe hierarchies
such as Thunderbolt outside the platform [1]. Previously these internal
devices were marked as "untrusted" the same as devices downstream from
them.
Use the ACPI or DT information to identify external-facing devices, but
only mark the devices *downstream* from them as "untrusted" [2]. The
external-facing device itself is no longer marked as untrusted.
[1] https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-externally-exposed-pcie-root-ports
[2] https://lore.kernel.org/linux-pci/
20200610230906.GA1528594@bjorn-Precision-5520/
Link: https://lore.kernel.org/r/20200707224604.3737893-3-rajatja@google.com
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
NULL,
};
-static inline bool has_untrusted_dev(void)
+static inline bool has_external_pci(void)
{
struct pci_dev *pdev = NULL;
for_each_pci_dev(pdev)
- if (pdev->untrusted)
+ if (pdev->external_facing)
return true;
return false;
static int __init platform_optin_force_iommu(void)
{
- if (!dmar_platform_optin() || no_platform_optin || !has_untrusted_dev())
+ if (!dmar_platform_optin() || no_platform_optin || !has_external_pci())
return 0;
if (no_iommu || dmar_disabled)
} else {
node = of_node_get(bus->self->dev.of_node);
if (node && of_property_read_bool(node, "external-facing"))
- bus->self->untrusted = true;
+ bus->self->external_facing = true;
}
bus->dev.of_node = node;
ACPI_FREE(obj);
}
-static void pci_acpi_set_untrusted(struct pci_dev *dev)
+static void pci_acpi_set_external_facing(struct pci_dev *dev)
{
u8 val;
/*
* These root ports expose PCIe (including DMA) outside of the
- * system so make sure we treat them and everything behind as
- * untrusted.
+ * system. Everything downstream from them is external.
*/
if (val)
- dev->untrusted = 1;
+ dev->external_facing = 1;
}
static void pci_acpi_setup(struct device *dev)
return;
pci_acpi_optimize_delay(pci_dev, adev->handle);
- pci_acpi_set_untrusted(pci_dev);
+ pci_acpi_set_external_facing(pci_dev);
pci_acpi_add_edr_notifier(pci_dev);
pci_acpi_add_pm_notifier(adev, pci_dev);
* untrusted as well.
*/
parent = pci_upstream_bridge(dev);
- if (parent && parent->untrusted)
+ if (parent && (parent->untrusted || parent->external_facing))
dev->untrusted = true;
}
* mappings to make sure they cannot access arbitrary memory.
*/
unsigned int untrusted:1;
+ /*
+ * Info from the platform, e.g., ACPI or device tree, may mark a
+ * device as "external-facing". An external-facing device is
+ * itself internal but devices downstream from it are external.
+ */
+ unsigned int external_facing:1;
unsigned int broken_intx_masking:1; /* INTx masking can't be used */
unsigned int io_window_1k:1; /* Intel bridge 1K I/O windows */
unsigned int irq_managed:1;