Re: [PATCH net] octeontx2-pf: check DMAC extraction support before filtering

[Harshitha Ramamurthy]

On Thu, Jun 25, 2026 at 10:30 AM <nshettyj@xxxxxxxxxxx> wrote:
>
> From: Suman Ghosh <sumang@xxxxxxxxxxx>
>
> Currently, configuring a VF MAC address via the PF (e.g., 'ip link
> set <pf> vf 0 mac <mac>') blindly attempts to install a DMAC-based
> hardware filter. However, the hardware parser profile might not
> support DMAC extraction.
>
> Check if the hardware parsing profile supports DMAC extraction
> before adding the filter. Additionally, emit a warning message
> to inform the operator if the MAC filter installation fails due
> to missing DMAC extraction support.
>
> Fixes: f0c2982aaf98 ("octeontx2-pf: Add support for SR-IOV management functions")
> Signed-off-by: Suman Ghosh <sumang@xxxxxxxxxxx>
> Signed-off-by: Nitin Shetty J <nshettyj@xxxxxxxxxxx>
> ---
>  .../ethernet/marvell/octeontx2/nic/otx2_pf.c  | 34 +++++++++++++++++++
>  1 file changed, 34 insertions(+)
>
> diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
> index b63df5737ff2..8e4435d9e520 100644
> --- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
> +++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_pf.c
> @@ -2546,6 +2546,8 @@ static int otx2_do_set_vf_mac(struct otx2_nic *pf, int vf, const u8 *mac)
>  static int otx2_set_vf_mac(struct net_device *netdev, int vf, u8 *mac)
>  {
>         struct otx2_nic *pf = netdev_priv(netdev);
> +       struct npc_get_field_status_req *req;
> +       struct npc_get_field_status_rsp *rsp;
>         struct pci_dev *pdev = pf->pdev;
>         struct otx2_vf_config *config;
>         int ret;
> @@ -2559,6 +2561,38 @@ static int otx2_set_vf_mac(struct net_device *netdev, int vf, u8 *mac)
>         if (!is_valid_ether_addr(mac))
>                 return -EINVAL;
>
> +       /* Skip installing the DMAC filter if the hardware parser profile
> +        * does not support DMAC extraction.
> +        */
> +       mutex_lock(&pf->mbox.lock);
> +       req = otx2_mbox_alloc_msg_npc_get_field_status(&pf->mbox);
> +       if (!req) {
> +               mutex_unlock(&pf->mbox.lock);
> +               return -ENOMEM;
> +       }
> +
> +       req->field = NPC_DMAC;
> +       if (otx2_sync_mbox_msg(&pf->mbox)) {
> +               mutex_unlock(&pf->mbox.lock);
> +               return -EINVAL;
> +       }
> +
> +       rsp = (struct npc_get_field_status_rsp *)otx2_mbox_get_rsp
> +              (&pf->mbox.mbox, 0, &req->hdr);
> +       if (IS_ERR(rsp)) {
> +               mutex_unlock(&pf->mbox.lock);
> +               return PTR_ERR(rsp);
> +       }
> +
> +       if (!rsp->enable) {
> +               mutex_unlock(&pf->mbox.lock);
> +               netdev_warn(netdev, "VF %d MAC filter not installed: DMAC extraction not supported by parser profile\n",
> +                           vf);
> +               return 0;

Is the intent to return success here even though the MAC address was
not programmed?

> +       }
> +
> +       mutex_unlock(&pf->mbox.lock);
> +

Why not move all these checks into the otx2_do_set_vf_mac() since that
anyway acquires the pf->mbox.lock? That way you could also fold all
the mutex_unlock() calls introduced in the error paths in this patch
into the existing goto-out in that function.

>         config = &pf->vf_configs[vf];
>         ether_addr_copy(config->mac, mac);
>
> --
> 2.48.1
>
>