lkml.org 
[lkml]   [2019]   [Oct]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 0/2] iommu/vt-d: Select PCI_PRI for INTEL_IOMMU_SVM
On Wed Oct 09 19, Bjorn Helgaas wrote:
>From: Bjorn Helgaas <bhelgaas@google.com>
>
>I think intel-iommu.c depends on CONFIG_AMD_IOMMU in an undesirable way:
>
>When CONFIG_INTEL_IOMMU_SVM=y, iommu_enable_dev_iotlb() calls PRI
>interfaces (pci_reset_pri() and pci_enable_pri()), but those are only
>implemented when CONFIG_PCI_PRI is enabled. If CONFIG_PCI_PRI is not
>enabled, there are stubs that just return failure.
>
>The INTEL_IOMMU_SVM Kconfig does nothing with PCI_PRI, but AMD_IOMMU
>selects PCI_PRI. So if AMD_IOMMU is enabled, intel-iommu.c gets the full
>PRI interfaces. If AMD_IOMMU is not enabled, it gets the PRI stubs.
>
>This seems wrong. The first patch here makes INTEL_IOMMU_SVM select
>PCI_PRI so intel-iommu.c always gets the full PRI interfaces.
>
>The second patch moves pci_prg_resp_pasid_required(), which simply returns
>a bit from the PCI capability, from #ifdef CONFIG_PCI_PASID to #ifdef
>CONFIG_PCI_PRI. This is related because INTEL_IOMMU_SVM already *does*
>select PCI_PASID, so it previously always got pci_prg_resp_pasid_required()
>even though it got stubs for other PRI things.
>
>Since these are related and I have several follow-on ATS-related patches in
>the queue, I'd like to take these both via the PCI tree.
>
>Bjorn Helgaas (2):
> iommu/vt-d: Select PCI_PRI for INTEL_IOMMU_SVM
> PCI/ATS: Move pci_prg_resp_pasid_required() to CONFIG_PCI_PRI
>
> drivers/iommu/Kconfig | 1 +
> drivers/pci/ats.c | 55 +++++++++++++++++++----------------------
> include/linux/pci-ats.h | 11 ++++-----
> 3 files changed, 31 insertions(+), 36 deletions(-)
>
>--
>2.23.0.581.g78d2f28ef7-goog
>
>_______________________________________________
>iommu mailing list
>iommu@lists.linux-foundation.org
>https://lists.linuxfoundation.org/mailman/listinfo/iommu

Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>

\
 
 \ /
  Last update: 2019-10-10 01:51    [W:0.042 / U:9.540 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site