ixgbe: fix vf lookup

commit a4b08329c74985e5cc3a44b6d2b2c59444ed8079 upstream.

Recent addition of code to find already allocated VFs failed to take
account that systems with 2 or more multi-port SR-IOV capable controllers
might have already enabled VFs.  Make sure that the VFs the function is
finding are actually subordinate to the particular instance of the adapter
that is looking for them and not subordinate to some device that has
previously enabled SR-IOV.

This bug exists in 3.2 stable as well as 3.3 release candidates.

Reported-by: David Ahern <daahern@cisco.com>
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Robert E Garrett <robertX.e.garrett@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
index 00fcd39ad666b6c289379e401800438347952dd7..e5713562de1a312e47dd21f171d70557a209f2eb 100644 (file)
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
@@ -67,7 +67,8 @@ static int ixgbe_find_enabled_vfs(struct ixgbe_adapter *adapter)
        vf_devfn = pdev->devfn + 0x80;
        pvfdev = pci_get_device(IXGBE_INTEL_VENDOR_ID, device_id, NULL);
        while (pvfdev) {
-               if (pvfdev->devfn == vf_devfn)
+               if (pvfdev->devfn == vf_devfn &&
+                   (pvfdev->bus->number >= pdev->bus->number))
                        vfs_found++;
                vf_devfn += 2;
                pvfdev = pci_get_device(IXGBE_INTEL_VENDOR_ID,