2021-03-14 20:20:45

by Kyung Min Park

Subject: [PATCH] iommu/vt-d: Disable SVM when ATS/PRI/PASID are not enabled in the device

Currently, the Intel VT-d supports Shared Virtual Memory (SVM) only when
IO page fault is supported. Otherwise, shared memory pages can not be
swapped out and need to be pinned. The device needs the Address Translation
Service (ATS), Page Request Interface (PRI) and Process Address Space
Identifier (PASID) capabilities to be enabled to support IO page fault.

Disable SVM when ATS, PRI and PASID are not enabled in the device.

Signed-off-by: Kyung Min Park <[email protected]>
---
drivers/iommu/intel/iommu.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index ee0932307d64..956a02eb40b4 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5380,6 +5380,9 @@ intel_iommu_dev_enable_feat(struct device *dev, enum iommu_dev_features feat)
if (!info)
return -EINVAL;

+ if (!info->pasid_enabled || !info->pri_enabled || !info->ats_enabled)
+ return -EINVAL;
+
if (info->iommu->flags & VTD_FLAG_SVM_CAPABLE)
return 0;
}
--
2.17.1

2021-03-15 00:45:52

by Lu Baolu

Subject: Re: [PATCH] iommu/vt-d: Disable SVM when ATS/PRI/PASID are not enabled in the device

On 3/15/21 4:15 AM, Kyung Min Park wrote:
> Currently, the Intel VT-d supports Shared Virtual Memory (SVM) only when
> IO page fault is supported. Otherwise, shared memory pages can not be
> swapped out and need to be pinned. The device needs the Address Translation
> Service (ATS), Page Request Interface (PRI) and Process Address Space
> Identifier (PASID) capabilities to be enabled to support IO page fault.
>
> Disable SVM when ATS, PRI and PASID are not enabled in the device.
>
> Signed-off-by: Kyung Min Park <[email protected]>
> ---
> drivers/iommu/intel/iommu.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index ee0932307d64..956a02eb40b4 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -5380,6 +5380,9 @@ intel_iommu_dev_enable_feat(struct device *dev, enum iommu_dev_features feat)
> if (!info)
> return -EINVAL;
>
> + if (!info->pasid_enabled || !info->pri_enabled || !info->ats_enabled)
> + return -EINVAL;
> +
> if (info->iommu->flags & VTD_FLAG_SVM_CAPABLE)
> return 0;
> }
>

Thanks for the patch.

Acked-by: Lu Baolu <[email protected]>

Best regards,
baolu

2021-03-18 10:26:57

by Joerg Roedel

Subject: Re: [PATCH] iommu/vt-d: Disable SVM when ATS/PRI/PASID are not enabled in the device

On Sun, Mar 14, 2021 at 01:15:34PM -0700, Kyung Min Park wrote:
> Currently, the Intel VT-d supports Shared Virtual Memory (SVM) only when
> IO page fault is supported. Otherwise, shared memory pages can not be
> swapped out and need to be pinned. The device needs the Address Translation
> Service (ATS), Page Request Interface (PRI) and Process Address Space
> Identifier (PASID) capabilities to be enabled to support IO page fault.
>
> Disable SVM when ATS, PRI and PASID are not enabled in the device.
>
> Signed-off-by: Kyung Min Park <[email protected]>

Applied, thanks.