Re: [PATCH 0/4] PCI, iommu: Factor 'untrusted' check for ATS enablement

Raj, Ashok
2020-05-18T16:31:17Z

On Mon, May 18, 2020 at 04:47:17PM +0100, David Woodhouse wrote:
> On Fri, 2020-05-15 at 10:19 -0700, Raj, Ashok wrote:
> > Hi Christoph
> >
> > On Fri, May 15, 2020 at 08:43:51AM -0700, Christoph Hellwig wrote:
> > > Can you please lift the untrusted flag into struct device? It really
> > > isn't a PCI specific concept, and we should not have code poking into
> > > pci_dev all over the iommu code.
> >
> > Just for clarification: All IOMMU's today mostly pertain to only PCI devices
> > and for devices that aren't PCI like HPET for instance we give a PCI
> > identifier. Facilities like ATS for instance require the platform to have
> > an IOMMU.
> >
> > what additional problems does moving this to struct device solve?
>
> Even the Intel IOMMU supports ACPI devices for which there is no struct
> pci_dev; only a B/D/F in the ANDD record indicating which entry in the
> context table to use.

Yes, spaced out :-).. just don't work on those platforms on a daily
basis and its easy to forget :-(