diff options
| author | Kevin Bowling <kbowling@FreeBSD.org> | 2026-07-28 23:29:35 +0000 |
|---|---|---|
| committer | Kevin Bowling <kbowling@FreeBSD.org> | 2026-07-30 00:40:05 +0000 |
| commit | e795a31cb4d66368bdbe5ac7f61c0899d3ed39f8 (patch) | |
| tree | 97a39d4aee08b7a537f5c5fdec8a82c2cb52ae6c | |
| parent | fd594981c55b3a4e316e72265065566a54d40d38 (diff) | |
pci_iov: Permit non-ARI VFs on a secondary bus
A non-zero VF device number does not always require ARI. The Intel
82576 and I350 [1] explicitly support a non-ARI layout that places VFs
on the next bus.
Check every requested VF RID and reject a non-zero device only when it
is on the PF bus. This retains the ARI guard for invalid same-bus
layouts while permitting the documented second-bus layout.
[1] Intel I350 Datasheet, sections 7.8.2.6.1.2, 9.6.4.6
Sponsored by: BBOX.io
| -rw-r--r-- | sys/dev/pci/pci_iov.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/sys/dev/pci/pci_iov.c b/sys/dev/pci/pci_iov.c index 0e6104fe37f2..932d83536b7f 100644 --- a/sys/dev/pci/pci_iov.c +++ b/sys/dev/pci/pci_iov.c @@ -759,9 +759,24 @@ pci_iov_config(struct cdev *cdev, struct pci_iov_arg *arg) } } - if (!ari_enabled && PCI_RID2SLOT(last_rid) != 0) { - error = ENOSPC; - goto out; + if (!ari_enabled) { + uint16_t vf_rid; + + /* + * Without ARI, VFs on the PF's bus must use device 0. + * VFs on another bus use the conventional device/function + * encoding and may have a non-zero device number. For + * example, Intel 82576 and I350 VFs start at device 16 on + * the next bus when ARI is unavailable. + */ + vf_rid = first_rid; + for (i = 0; i < num_vfs; i++, vf_rid += rid_stride) { + if (PCI_RID2BUS(vf_rid) == pci_get_bus(dev) && + PCI_RID2SLOT(vf_rid) != 0) { + error = ENOSPC; + goto out; + } + } } iov_ctl = IOV_READ(dinfo, PCIR_SRIOV_CTL, 2); |