diff mbox series

[1/2] iommu/vt-d: Select PCI_PRI for INTEL_IOMMU_SVM

Message ID 20191009224551.179497-2-helgaas@kernel.org
State Accepted
Delegated to: Bjorn Helgaas
Headers show
Series iommu/vt-d: Select PCI_PRI for INTEL_IOMMU_SVM | expand

Commit Message

Bjorn Helgaas Oct. 9, 2019, 10:45 p.m. UTC 
From: Bjorn Helgaas <bhelgaas@google.com>

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.

Previously INTEL_IOMMU_SVM selected PCI_PASID but not PCI_PRI, so the state
of PCI_PRI depended on whether AMD_IOMMU (which selects PCI_PRI) was
enabled or PCI_PRI was enabled explicitly.

The behavior of iommu_enable_dev_iotlb() should not depend on whether
AMD_IOMMU is enabled.  Make it predictable by having INTEL_IOMMU_SVM select
PCI_PRI so iommu_enable_dev_iotlb() always uses the full implementations of
PRI interfaces.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 drivers/iommu/Kconfig | 1 +
 1 file changed, 1 insertion(+)

Comments

Kuppuswamy Sathyanarayanan Oct. 9, 2019, 11:42 p.m. UTC | #1 
On 10/9/19 3:45 PM, Bjorn Helgaas wrote:
> From: Bjorn Helgaas <bhelgaas@google.com>
>
> 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.
>
> Previously INTEL_IOMMU_SVM selected PCI_PASID but not PCI_PRI, so the state
> of PCI_PRI depended on whether AMD_IOMMU (which selects PCI_PRI) was
> enabled or PCI_PRI was enabled explicitly.
>
> The behavior of iommu_enable_dev_iotlb() should not depend on whether
> AMD_IOMMU is enabled.  Make it predictable by having INTEL_IOMMU_SVM select
> PCI_PRI so iommu_enable_dev_iotlb() always uses the full implementations of
> PRI interfaces.
>
> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Looks good to me.

Reviewed-by: Kuppuswamy Sathyanarayanan 
<sathyanarayanan.kuppuswamy@linux.intel.com>

> ---
>   drivers/iommu/Kconfig | 1 +
>   1 file changed, 1 insertion(+)
>
> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> index e3842eabcfdd..b183c9f916b0 100644
> --- a/drivers/iommu/Kconfig
> +++ b/drivers/iommu/Kconfig
> @@ -207,6 +207,7 @@ config INTEL_IOMMU_SVM
>   	bool "Support for Shared Virtual Memory with Intel IOMMU"
>   	depends on INTEL_IOMMU && X86
>   	select PCI_PASID
> +	select PCI_PRI
>   	select MMU_NOTIFIER
>   	help
>   	  Shared Virtual Memory (SVM) provides a facility for devices
diff mbox series

Patch

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index e3842eabcfdd..b183c9f916b0 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -207,6 +207,7 @@  config INTEL_IOMMU_SVM
 	bool "Support for Shared Virtual Memory with Intel IOMMU"
 	depends on INTEL_IOMMU && X86
 	select PCI_PASID
+	select PCI_PRI
 	select MMU_NOTIFIER
 	help
 	  Shared Virtual Memory (SVM) provides a facility for devices