Hello Folks, On Tue, Feb 1, 2022 at 6:01 PM Rajat Jain <rajatja@xxxxxxxxxx> wrote: > > Today the pci_dev->untrusted is set for any devices sitting downstream > an external facing port (determined via "ExternalFacingPort" or the > "external-facing" properties). > > However, currently there is no way for internal devices to be marked as > untrusted. > > There are use-cases though, where a platform would like to treat an > internal device as untrusted (perhaps because it runs untrusted firmware > or offers an attack surface by handling untrusted network data etc). > > Introduce a new "UntrustedDevice" property that can be used by the > firmware to mark any device as untrusted. Just to unite the threads (from https://www.spinics.net/lists/linux-pci/msg120221.html). I did reach out to Microsoft but they haven't acknowledged my email. I also pinged them again yesterday, but I suspect I may not be able to break the ice. So this patch may be ready to go in my opinion. I don't see any outstanding comments on this patch, but please let me know if you have any comments. Thanks & Best Regards, Rajat > > Signed-off-by: Rajat Jain <rajatja@xxxxxxxxxx> > --- > v2: * Also use the same property for device tree based systems. > * Add documentation (next patch) > > drivers/pci/of.c | 2 ++ > drivers/pci/pci-acpi.c | 1 + > drivers/pci/pci.c | 9 +++++++++ > drivers/pci/pci.h | 2 ++ > 4 files changed, 14 insertions(+) > > diff --git a/drivers/pci/of.c b/drivers/pci/of.c > index cb2e8351c2cc..e8b804664b69 100644 > --- a/drivers/pci/of.c > +++ b/drivers/pci/of.c > @@ -24,6 +24,8 @@ void pci_set_of_node(struct pci_dev *dev) > dev->devfn); > if (dev->dev.of_node) > dev->dev.fwnode = &dev->dev.of_node->fwnode; > + > + pci_set_untrusted(dev); > } > > void pci_release_of_node(struct pci_dev *dev) > diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c > index a42dbf448860..2bffbd5c6114 100644 > --- a/drivers/pci/pci-acpi.c > +++ b/drivers/pci/pci-acpi.c > @@ -1356,6 +1356,7 @@ void pci_acpi_setup(struct device *dev, struct acpi_device *adev) > > pci_acpi_optimize_delay(pci_dev, adev->handle); > pci_acpi_set_external_facing(pci_dev); > + pci_set_untrusted(pci_dev); > pci_acpi_add_edr_notifier(pci_dev); > > pci_acpi_add_pm_notifier(adev, pci_dev); > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index 9ecce435fb3f..41e887c27004 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -6869,3 +6869,12 @@ static int __init pci_realloc_setup_params(void) > return 0; > } > pure_initcall(pci_realloc_setup_params); > + > +void pci_set_untrusted(struct pci_dev *pdev) > +{ > + u8 val; > + > + if (!device_property_read_u8(&pdev->dev, "UntrustedDevice", &val) > + && val) > + pdev->untrusted = 1; > +} > diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h > index 3d60cabde1a1..6c273ce5e0ba 100644 > --- a/drivers/pci/pci.h > +++ b/drivers/pci/pci.h > @@ -761,4 +761,6 @@ static inline pci_power_t mid_pci_get_power_state(struct pci_dev *pdev) > } > #endif > > +void pci_set_untrusted(struct pci_dev *pdev); > + > #endif /* DRIVERS_PCI_H */ > -- > 2.35.0.rc2.247.g8bbb082509-goog >
