Re: [Intel-wired-lan] [PATCH iwl-next v3] i40e: add ability to reset vf for tx and rx mdd events

[Michal Schmidt]

On Fri, Aug 30, 2024 at 9:28 PM Aleksandr Loktionov
<aleksandr.loktio...@intel.com> wrote:
>
> In cases when vf sends malformed packets that are classified as
> malicious, sometimes it causes tx queue to freeze. This frozen queue can be
> stuck for several minutes being unusable. When mdd event occurs, there is a
> posibility to perform a graceful vf reset to quickly bring vf back to
> operational state.
>
> Currently vf iqueues are being disabled if mdd event occurs.
> Add the ability to reset vf if tx or rx mdd occurs.
> Add mdd events logging throttling /* avoid dmesg polution */.
> Unify tx rx mdd messages formats.
>
> Co-developed-by: Jan Sokolowski <jan.sokolow...@intel.com>
> Signed-off-by: Jan Sokolowski <jan.sokolow...@intel.com>
> Co-developed-by: Padraig J Connolly <padraig.j.conno...@intel.com>
> Signed-off-by:  Padraig J Connolly <padraig.j.conno...@intel.com>
> Signed-off-by: Aleksandr Loktionov <aleksandr.loktio...@intel.com>
> ---

Thanks, we need this. ice has the same ability.
Just one question about the patch:

[...]
>  static void i40e_handle_mdd_event(struct i40e_pf *pf)
>  {
>         struct i40e_hw *hw = &pf->hw;
>         bool mdd_detected = false;
>         struct i40e_vf *vf;
>         u32 reg;
>         int i;
>
> -       if (!test_bit(__I40E_MDD_EVENT_PENDING, pf->state))
> +       if (!test_and_clear_bit(__I40E_MDD_EVENT_PENDING, pf->state)) {

OK, using test_and_clear_bit is good, but ...:

[...]
>
>         /* re-enable mdd interrupt cause */
>         clear_bit(__I40E_MDD_EVENT_PENDING, pf->state);

Here the bit is cleared again. Why?

>         reg = rd32(hw, I40E_PFINT_ICR0_ENA);
>         reg |=  I40E_PFINT_ICR0_ENA_MAL_DETECT_MASK;
>         wr32(hw, I40E_PFINT_ICR0_ENA, reg);
>         i40e_flush(hw);
> +
> +       i40e_print_vfs_mdd_events(pf);
>  }

Michal