On Tue, Apr 20, 2021 at 07:10:06AM +0100, Christoph Hellwig wrote: > On Mon, Apr 19, 2021 at 05:30:49PM -0700, Rajat Jain wrote: > > The current flag name "untrusted" is not correct as it is populated > > using the firmware property "external-facing" for the parent ports. In > > other words, the firmware only says which ports are external facing, so > > the field really identifies the devices as external (vs internal). > > > > Only field renaming. No functional change intended. > > I don't think this is a good idea. First the field should have been > added to the generic struct device as requested multiple times before.
Fair point. There isn't anything PCI-specific about this idea. The ACPI "ExternalFacingPort" and DT "external-facing" are currently only defined for PCI devices, but could be applied elsewhere. > Right now this requires horrible hacks in the IOMMU code to get at the > pci_dev, and also doesn't scale to various other potential users. Agreed, this is definitely suboptimal. Do you have other users in mind? Maybe they could help inform the plan. > Second the untrusted is objectively a better name. Because untrusted > is how we treat the device, which is what mattes. External is just > how we come to that conclusion. The decision to treat "external" as being "untrusted" is a little bit of policy that the PCI core really doesn't care about, so I think it does make some sense to let the places that *do* care decide what to trust based on "external" and possibly other factors, e.g., whether the device is a BMC or processes untrusted data, etc. But I guess it makes sense to wait until we have a better motivation before renaming it, since we don't gain any functionality here. Bjorn
