Re: [PATCH v2 0/3] pci: ACS fixes & quirks

From: Alex Williamson
Date: Tue Jul 23 2013 - 11:47:39 EST



This series was ack'd by Don. I haven't heard reports of any problems.
What more needs to be done here? Bjorn? Thanks,

Alex


On Mon, 2013-07-08 at 10:17 -0600, Alex Williamson wrote:
> Ping. Comments?
>
> On Thu, 2013-06-27 at 16:39 -0600, Alex Williamson wrote:
> > v2:
> >
> > Revised patch 1/ to match comments from Bjorn. PCIe event collectors
> > and PCIe-to-PCI bridges now indicate that they do not support ACS.
> > I've reached out to try to get clarification on this, but I think it's
> > reasonable to proceed with a conservative approach until then. I also
> > added PCI-to-PCIe bridges for the sake of being complete. Also added
> > more comments about the purpose and behavior of pci_acs_enabled(). If
> > I've overlooked anything else that needs to be addressed, please let
> > me know.
> >
> > Patch 2/ had no comments, it's unchanged.
> >
> > Patch 3/ is added. This was sent as an RFC nearly a year ago and
> > Joerg confirmed for us that these devices do not support p2p on AMD
> > systems with AMD IOMMU. We can't simply use iommu_present() to test
> > for an IOMMU because it's setup just after we need this function.
> > Instead we test for the ACPI IVRS table that describes the IOMMU. It
> > would probably suffice to skip an actual AMD IOMMU check, but I don't
> > want it to later come bite us if these ASICs get re-used, maybe with
> > a different IOMMU, and don't make the same guarantees.
> >
> > Joerg, I was also curious back when we investigated this patch if the
> > same rules hold true for these other southbridge devices:
> >
> > 1002:43a0 SB700/SB800/SB900 PCI to PCI bridge (PCIE port 0)
> > 1002:43a1 SB700/SB800/SB900 PCI to PCI bridge (PCIE port 1)
> > 1002:43a2 SB900 PCI to PCI bridge (PCIE port 2)
> > 1002:43a3 SB900 PCI to PCI bridge (PCIE port 3)
> >
> > If you remember or have contacts to poke, I'd be happy to follow-up
> > with another patch to add them. Thanks,
> >
> > Alex
> >
> > ---
> >
> > Alex Williamson (3):
> > pci: Fix flaw in pci_acs_enabled()
> > pci: Differentiate ACS controllable from enabled
> > pci: ACS quirk for AMD southbridge
> >
> >
> > drivers/pci/pci.c | 93 +++++++++++++++++++++++++++++++++++++++++---------
> > drivers/pci/quirks.c | 50 +++++++++++++++++++++++++++
> > 2 files changed, 127 insertions(+), 16 deletions(-)
>
>



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/