Thank you for reporting the issue and the patch. Please see comments below.
On Sat, Jan 10, 2026 at 11:15:10PM +0000, Max Tottenham wrote: > When probing an SF as a vDPA device, mlx5_roce_disable() targets the > parent PF address (via mlx5_dev_to_pci_str). This incorrectly attempts > to disable ROCE on the parent PF rather than the SF itself. > > This causes vDPA probe failures when the parent PF already has an open > IB context (e.g., probed for uplink ports or SF representors). > > For SubFunctions, ROCE is configured via devlink parameters > (enable_roce) before device creation. Skip the runtime ROCE disable > for auxiliary devices since the devlink configuration is already in > effect and targeting the parent PF is incorrect. > > Signed-off-by: Max Tottenham <[email protected]> > --- > drivers/common/mlx5/linux/mlx5_common_os.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/common/mlx5/linux/mlx5_common_os.c > b/drivers/common/mlx5/linux/mlx5_common_os.c > index 2867e21618..6fa12e06eb 100644 > --- a/drivers/common/mlx5/linux/mlx5_common_os.c > +++ b/drivers/common/mlx5/linux/mlx5_common_os.c > @@ -690,6 +690,19 @@ mlx5_roce_disable(const struct rte_device *dev) > { > char pci_addr[PCI_PRI_STR_SIZE] = { 0 }; > > + /* > + * For auxiliary devices (SFs), ROCE is configured via devlink > + * parameters (enable_roce) before device creation. Skip runtime > + * ROCE disable since mlx5_dev_to_pci_str() returns the parent PF > + * address, not the SF - disabling ROCE on the parent PF is both > + * incorrect and may fail if the PF already has an active IB context. > + */ > + if (!mlx5_dev_is_pci(dev)) { > + DRV_LOG(INFO, "Skipping ROCE disable for auxiliary device > \"%s\"", > + dev->name); > + return 0; > + } The logic has a bug as you mentioned, but I don't think it would be a good idea to not disable ROCE automatically for SFs. Especially since, IIUC, enable_roce option value is not inherited from PF when new SF is created and probed. It'll move more responsibility to the user regarding port configuration. In my opinion mlx5_roce_disable() should have split logic like so: if mlx5_dev_is_pci(dev) // for PCI devices continue as usual: // try disabling ROCE through netlink or sysfs else // for SFs: try disabling ROCE through netlink This would require some adjustments in mlx5_nl_roce_disable() and related code. Specifically, devlink attributes should be adjusted when disabling ROCE for auxiliary devices: - DEVLINK_ATTR_BUS_NAME = "auxiliary" - DEVLINK_ATTR_DEV_NAME = device name from rte_device->name Would you be able to make the necessary changes? > + > if (mlx5_dev_to_pci_str(dev, pci_addr, sizeof(pci_addr)) < 0) > return -rte_errno; > /* Firstly try to disable ROCE by Netlink and fallback to sysfs. */ > -- > 2.51.2 > Best regards, Dariusz Sosnowski
