On Tue, Apr 12, 2022 at 12:25:44PM -0600, Alex Williamson wrote:
> On Mon, 11 Apr 2022 10:56:31 -0300
> Jason Gunthorpe <jgg@xxxxxxxxxx> wrote:
>
> > @@ -1732,10 +1705,28 @@ static int vfio_pci_bus_notifier(struct notifier_block *nb,
> > static int vfio_pci_vf_init(struct vfio_pci_core_device *vdev)
> > {
> > struct pci_dev *pdev = vdev->pdev;
> > + struct vfio_pci_core_device *cur;
> > + struct pci_dev *physfn;
> > int ret;
> >
> > - if (!pdev->is_physfn)
> > + if (!pdev->is_physfn) {
> > + /*
> > + * If this VF was created by our vfio_pci_core_sriov_configure()
> > + * then we can find the PF vfio_pci_core_device now, and due to
> > + * the locking in pci_disable_sriov() it cannot change until
> > + * this VF device driver is removed.
> > + */
> > + physfn = pci_physfn(vdev->pdev);
> > + mutex_lock(&vfio_pci_sriov_pfs_mutex);
> > + list_for_each_entry (cur, &vfio_pci_sriov_pfs, sriov_pfs_item) {
> > + if (cur->pdev == physfn) {
> > + vdev->sriov_pf_core_dev = cur;
> > + break;
> > + }
> > + }
> > + mutex_unlock(&vfio_pci_sriov_pfs_mutex);
> > return 0;
> > + }
> >
> > vdev->vf_token = kzalloc(sizeof(*vdev->vf_token), GFP_KERNEL);
> > if (!vdev->vf_token)
>
> One more comment on final review; are we equating !is_physfn to
> is_virtfn above? This branch was originally meant to kick out both VFs
> and non-SRIOV PFs. Calling pci_physfn() on a !is_virtfn device will
> return itself, so we should never find a list match, but we also don't
> need to look for a match for !is_virtfn, so it's a bit confusing and
> slightly inefficient. Should the new code be added in a separate
> is_virtfn branch above the existing !is_physfn test? Thanks,
I started at it for a while and came the same conclusion, I
misunderstood that is_physfn is really trying to be
is_sriov_physfn.. So not a bug, but not really clear code.
I added this, I'll repost it.
diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index 8bf0f18e668a32..3c6493957abe19 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -1709,7 +1709,7 @@ static int vfio_pci_vf_init(struct vfio_pci_core_device *vdev)
struct pci_dev *physfn;
int ret;
- if (!pdev->is_physfn) {
+ if (pdev->is_virtfn) {
/*
* If this VF was created by our vfio_pci_core_sriov_configure()
* then we can find the PF vfio_pci_core_device now, and due to
@@ -1728,6 +1728,10 @@ static int vfio_pci_vf_init(struct vfio_pci_core_device *vdev)
return 0;
}
+ /* Not a SRIOV PF */
+ if (!pdev->is_physfn)
+ return 0;
+
vdev->vf_token = kzalloc(sizeof(*vdev->vf_token), GFP_KERNEL);
if (!vdev->vf_token)
return -ENOMEM;
Thanks,
Jason
