1 files changed, 19 insertions, 0 deletions

diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 921db6f80340..e1949f7efd9c 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -789,6 +789,24 @@ static void pci_acpi_optimize_delay(struct pci_dev *pdev,
         ACPI_FREE(obj);
 }
 
+static void pci_acpi_set_untrusted(struct pci_dev *dev)
+{
+        u8 val;
+
+        if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
+                return;
+        if (device_property_read_u8(&dev->dev, "ExternalFacingPort", &val))
+                return;
+
+        /*
+         * These root ports expose PCIe (including DMA) outside of the
+         * system so make sure we treat them and everything behind as
+         * untrusted.
+         */
+        if (val)
+                dev->untrusted = 1;
+}
+
 static void pci_acpi_setup(struct device *dev)
 {
         struct pci_dev *pci_dev = to_pci_dev(dev);
@@ -798,6 +816,7 @@ 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_add_pm_notifier(adev, pci_dev);
         if (!adev->wakeup.flags.valid)