On Fri, Jan 21, 2022 at 03:41:17PM -0600, Bjorn Helgaas wrote: > [+cc Greg, Jean-Philippe, Mika, Pavel, Oliver, Joerg since they > commented on previous "external-facing" discussion] > > On Wed, Jan 19, 2022 at 04:04:09PM -0800, Rajat Jain wrote: > > Today the pci_dev->untrusted is set for any devices sitting downstream > > an external facing port (determined via "ExternalFacingPort" property). > > This however, disallows any internal devices to be marked as untrusted. > > This isn't stated quite accurately. "dev->untrusted" is currently set > only by set_pcie_untrusted(), when "dev" has an upstream bridge that > is either external-facing or untrusted. > > But that doesn't disallow or prevent internal devices from being > marked as untrusted; it just doesn't implement that. > > > 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). Who is making this policy decision? > > This patch introduces a new "UntrustedDevice" property that can be used > > by the firmware to mark any device as untrusted. Is this in the ACPI standard? If so, where? This notion of "trust" for PCI devices is crazy, as I have stated a number of times before. But at least you are not trying to say kernel code is trusted or not. thanks, greg k-h
