On Fri, Aug 18, 2017 at 11:04:33AM -0500, Bjorn Helgaas wrote: > [+cc Robin] > > This series looks fine to me as far as PCI is concerned, and I'd be > happy to take it via my tree given an ack from David for this IOMMU > piece. Alternatively, you can add my > > Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > > to the other patches if you want to take it via another tree. > > Robin raised a question about basically this same patch the first time > around. Not sure whether there's still an objection there. Ping, David, any thoughts on this patch? > On Thu, Aug 17, 2017 at 12:10:14PM -0600, Jon Derrick wrote: > > VMD child devices must use the VMD endpoint's ID as the requester. > > Because of this, there needs to be a way to link the parent VMD > > endpoint's iommu group and associated mappings to the VMD child devices > > such that attaching and detaching child devices modify the endpoint's > > mappings, while preventing early detaching on a singular device removal > > or unbinding. > > > > The reassignment of individual VMD child devices devices to VMs is > > outside the scope of VMD, but may be implemented in the future. For now > > it is best to prevent any such attempts. > > > > This patch prevents VMD child devices from returning an IOMMU, which > > prevents it from exposing an iommu_group sysfs directories and allowing > > subsequent binding by userspace-access drivers such as VFIO. > > > > Signed-off-by: Jon Derrick <jonathan.derrick@xxxxxxxxx> > > --- > > drivers/iommu/intel-iommu.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > > index 687f18f..94353a6e 100644 > > --- a/drivers/iommu/intel-iommu.c > > +++ b/drivers/iommu/intel-iommu.c > > @@ -901,6 +901,11 @@ static struct intel_iommu *device_to_iommu(struct device *dev, u8 *bus, u8 *devf > > struct pci_dev *pf_pdev; > > > > pdev = to_pci_dev(dev); > > + > > + /* VMD child devices currently cannot be handled individually */ > > + if (is_vmd(pdev->bus)) > > + return NULL; > > + > > /* VFs aren't listed in scope tables; we need to look up > > * the PF instead to find the IOMMU. */ > > pf_pdev = pci_physfn(pdev); > > -- > > 2.9.4 > >
