From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> commit 2e34673be0bd6bb0c6c496a861cbc3f7431e7ce3 upstream. 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@xxxxxxxxxxxxxxx Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> CC: stable@xxxxxxxxxxxxxxx # v5.5+ Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/pci/ats.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/pci/ats.c +++ b/drivers/pci/ats.c @@ -424,11 +424,12 @@ void pci_restore_pasid_state(struct pci_ 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 *p 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;