[PATCH v1 1/1] iommu/vt-d: Enable PRI only if the device enables PASID.

[sathyanarayanan . kuppuswamy]

From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>

Intel IOMMU Page Request Services (PRS) only works with devices which
supports/uses PASID. So enable PRI only if the device also enables
PASID support. For more details, Please check the implementation of PRQ
handler(prq_event_thread()) in intel-svm driver.

Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
---
 drivers/iommu/intel-iommu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 1457f931218e..ef1a646e0993 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -1402,7 +1402,8 @@ static void iommu_enable_dev_iotlb(struct device_domain_info *info)
 	if (info->pasid_supported && !pci_enable_pasid(pdev, info->pasid_supported & ~1))
 		info->pasid_enabled = 1;
 
-	if (info->pri_supported && !pci_reset_pri(pdev) && !pci_enable_pri(pdev, 32))
+	if (info->pri_supported && info->pasid_enabled &&
+	    !pci_reset_pri(pdev) && !pci_enable_pri(pdev, 32))
 		info->pri_enabled = 1;
 #endif
 	if (!pdev->untrusted && info->ats_supported &&
-- 
2.20.1