On Thu, Jun 20, 2013 at 10:15 AM, Joerg Roedel <j...@8bytes.org> wrote:
> On Thu, Jun 20, 2013 at 09:44:51AM -0600, Alex Williamson wrote:
>> On Thu, 2013-06-20 at 15:59 +0200, Joerg Roedel wrote:
>> > On Tue, May 28, 2013 at 12:40:20PM -0600, Alex Williamson wrote:
>> > > + if (!pci_is_root_bus(pdev->bus)) {
>> > > + struct pci_dev *parent = pdev->bus->self;
>> > > +
>> > > + if (pci_is_pcie(parent) &&
>> > > + pci_pcie_type(parent) != PCI_EXP_TYPE_PCI_BRIDGE)
>> > > + return true;
>> > > + }
>> >
>> > Hmm, that looks a bit dangerous.
>>
>> How so? The algorithm seems pretty simple and logical.
>
> It is simple, but it is still a heuristic that may fail at some point,
> no?
>
>> Actually, I believe Bjorn rejected the idea of a fixed list because this
>> problem is detectable. He also doesn't want me messing with quirks to
>> pci_is_pcie() in PCI because he wants a 1:1 relation between that and
>> having a PCIe capability. So, I'm stuck and this is where it's ended
>> up. Thanks,
>
> I think implementing such a list is much safer.
>
> Bjorn, why didn't you like that idea?
Sorry, I can't remember, and I haven't been able to find the
discussion where I said that. I think the current patches are all in
drivers/iommu, and if a list makes sense there, it's fine with me.
Bjorn
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
