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 751035b8dc ("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: 751035b8dc ("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+
This commit is contained in:
Kuppuswamy Sathyanarayanan 2020-01-29 11:14:00 -08:00 committed by Bjorn Helgaas
parent b9303bb199
commit 2e34673be0
1 changed files with 4 additions and 2 deletions
drivers/pci

View File

@ -424,11 +424,12 @@ void pci_restore_pasid_state(struct pci_dev *pdev)
int pci_pasid_features(struct pci_dev *pdev) int pci_pasid_features(struct pci_dev *pdev)
{ {
u16 supported; u16 supported;
int pasid = pdev->pasid_cap; int pasid;
if (pdev->is_virtfn) if (pdev->is_virtfn)
pdev = pci_physfn(pdev); pdev = pci_physfn(pdev);
pasid = pdev->pasid_cap;
if (!pasid) if (!pasid)
return -EINVAL; return -EINVAL;
@ -451,11 +452,12 @@ int pci_pasid_features(struct pci_dev *pdev)
int pci_max_pasids(struct pci_dev *pdev) int pci_max_pasids(struct pci_dev *pdev)
{ {
u16 supported; u16 supported;
int pasid = pdev->pasid_cap; int pasid;
if (pdev->is_virtfn) if (pdev->is_virtfn)
pdev = pci_physfn(pdev); pdev = pci_physfn(pdev);
pasid = pdev->pasid_cap;
if (!pasid) if (!pasid)
return -EINVAL; return -EINVAL;