Re: [net-intel-i40e] question about assignment overwrite

From: Mauro Rodrigues
Date: Wed Jun 07 2017 - 15:55:45 EST


On Wed, May 17, 2017 at 10:49:11PM -0700, Jeff Kirsher wrote:
> On Wed, 2017-05-17 at 15:48 -0500, Gustavo A. R. Silva wrote:
> > While looking into Coverity ID 1408956 I ran into the following
> > piece  
> > of code at drivers/net/ethernet/intel/i40e/i40e_main.c:8807:
> >
> > 8807        if (pf->hw.mac.type == I40E_MAC_X722) {
> > 8808                pf->flags |= I40E_FLAG_RSS_AQ_CAPABLE
> > 8809                             | I40E_FLAG_128_QP_RSS_CAPABLE
> > 8810                             | I40E_FLAG_HW_ATR_EVICT_CAPABLE
> > 8811                             | I40E_FLAG_OUTER_UDP_CSUM_CAPABLE
> > 8812                             | I40E_FLAG_WB_ON_ITR_CAPABLE
> > 8813                             |
> > I40E_FLAG_MULTIPLE_TCP_UDP_RSS_PCTYPE
> > 8814                             | I40E_FLAG_NO_PCI_LINK_CHECK
> > 8815                             | I40E_FLAG_USE_SET_LLDP_MIB
> > 8816                             | I40E_FLAG_GENEVE_OFFLOAD_CAPABLE
> > 8817                             | I40E_FLAG_PTP_L4_CAPABLE
> > 8818                             | I40E_FLAG_WOL_MC_MAGIC_PKT_WAKE;
> > 8819        } else if ((pf->hw.aq.api_maj_ver > 1) ||
> > 8820                   ((pf->hw.aq.api_maj_ver == 1) &&
> > 8821                    (pf->hw.aq.api_min_ver > 4))) {
> > 8822                /* Supported in FW API version higher than 1.4 */
> > 8823                pf->flags |= I40E_FLAG_GENEVE_OFFLOAD_CAPABLE;
> > 8824                pf->flags = I40E_FLAG_HW_ATR_EVICT_CAPABLE;
> > 8825        } else {
> > 8826                pf->flags = I40E_FLAG_HW_ATR_EVICT_CAPABLE;
> > 8827        }
> >
> > The issue here is that the assignment at line 8823 is overwritten
> > by  
> > the code at line 8824.
> >
> > I'm suspicious that line 8824 should be remove and a patch like the  
> > following can be applied:
> >
> > index d5c9c9e..48ffa73 100644
> > --- a/drivers/net/ethernet/intel/i40e/i40e_main.c
> > +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
> > @@ -8821,7 +8821,6 @@ static int i40e_sw_init(struct i40e_pf *pf)
> >                      (pf->hw.aq.api_min_ver > 4))) {
> >                  /* Supported in FW API version higher than 1.4 */
> >                  pf->flags |= I40E_FLAG_GENEVE_OFFLOAD_CAPABLE;
> > -               pf->flags = I40E_FLAG_HW_ATR_EVICT_CAPABLE;
> >          } else {
> >                  pf->flags = I40E_FLAG_HW_ATR_EVICT_CAPABLE;
> >          }
> >
> > What do you think?
>
> This issue is already fixed in my dev-queue branch on my next-queue
> tree.

Hi Jeff, are you planning to push this fix into net branch anytime soon?

Thanks,

Mauro