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authorKuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>2020-01-29 11:14:00 -0800
committerBjorn Helgaas <bhelgaas@google.com>2020-02-05 11:58:08 -0600
commit2e34673be0bd6bb0c6c496a861cbc3f7431e7ce3 (patch)
tree2396a39fd32329408f358366f05dfdd8c752fc61
parentb9303bb1990950bd2f49ec1c85c015b5b6aac24b (diff)
downloadlinux-2e34673be0bd6bb0c6c496a861cbc3f7431e7ce3.tar.gz
PCI/ATS: Use PF PASID for VFs
Per PCIe r5.0, sec 9.3.7.14, if a PF implements the PASID Capability, the
PF PASID configuration is shared by its VFs, and VFs must not implement
their own PASID Capability.  But commit 751035b8dc06 ("PCI/ATS: Cache PASID
Capability offset") changed pci_max_pasids() and pci_pasid_features() to
use the PASID Capability of the VF device instead of the associated PF
device.  This leads to IOMMU bind failures when pci_max_pasids() and
pci_pasid_features() are called for VFs.

In pci_max_pasids() and pci_pasid_features(), always use the PF PASID
Capability.

Fixes: 751035b8dc06 ("PCI/ATS: Cache PASID Capability offset")
Link: https://lore.kernel.org/r/fe891f9755cb18349389609e7fed9940fc5b081a.1580325170.git.sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v5.5+
-rw-r--r--drivers/pci/ats.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index 982b46f0a54d..b6f064c885c3 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -424,11 +424,12 @@ void pci_restore_pasid_state(struct pci_dev *pdev)
 int pci_pasid_features(struct pci_dev *pdev)
 {
 	u16 supported;
-	int pasid = pdev->pasid_cap;
+	int pasid;
 
 	if (pdev->is_virtfn)
 		pdev = pci_physfn(pdev);
 
+	pasid = pdev->pasid_cap;
 	if (!pasid)
 		return -EINVAL;
 
@@ -451,11 +452,12 @@ int pci_pasid_features(struct pci_dev *pdev)
 int pci_max_pasids(struct pci_dev *pdev)
 {
 	u16 supported;
-	int pasid = pdev->pasid_cap;
+	int pasid;
 
 	if (pdev->is_virtfn)
 		pdev = pci_physfn(pdev);
 
+	pasid = pdev->pasid_cap;
 	if (!pasid)
 		return -EINVAL;