Re: [dpdk-dev] [PATCH v2] net/ixgbe: initialize port even if mtu config fails

[Tudor Cornea <tudor.cornea@gmail.com>]

On Thu, 21 Oct 2021 at 18:33, Ferruh Yigit <ferruh.yigit@intel.com> wrote:

> On 10/20/2021 7:13 PM, Tudor Cornea wrote:
> > On a VMware ESXi 6.0 setup with an Intel 82599 NIC the ports don't
> > seem to initialize anymore, while running testpmd.
> >
> > Configuring Port 0 (socket 0)
> > ixgbevf_dev_rx_init(): Set max packet length to 1518 failed.
> > ixgbevf_dev_start(): Unable to initialize RX hardware (-22)
> > Fail to start port 0: Invalid argument
> > Configuring Port 1 (socket 0)
> > ixgbevf_dev_rx_init(): Set max packet length to 1518 failed.
> > ixgbevf_dev_start(): Unable to initialize RX hardware (-22)
> > Fail to start port 1: Invalid argument
> > Please stop the ports first
> >
> > If the call to ixgbevf_rlpml_set_vf fails and we return prematurely,
> > we will not be able to initialize the ports correctly.
> >
> > The behavior seems to have changed since the following commit:
> >
> > commit c77866a16904 ("net/ixgbe: detect failed VF MTU set")
> >
>
> Hi Tudor,
>
> We document this with explicit 'Fixes' tag, this also helps up to
> manage backporting patches to LTS releases, so updating as:
>
>      Fixes: 3a6bfc37eaf4 ("net/ice: support QoS config VF bandwidth in
> DCF")
>      Cc: stable@dpdk.org
>
> Also we use 'fix' verb in the patch title almost as keyword, again
> to help deciding which patch to backport, also to clarify impact of
> the patch, so will update patch title as:
>
>      net/ixgbe: fix port initialization if MTU config fails
>
>
> For more details please check contribution guide:
> https://doc.dpdk.org/guides/contributing/patches.html
>
> Thanks,
> ferruh
>
> > We can make this particular use case work correctly if we don't
> > return an error, which seems to be consistent with the overall
> > kernel ixgbevf implementation.
> >
> > [1]
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c#n2015
> >
>
> The code that this link references can change by time as code changes,
> I will update it as following to bind it a specific version (v5.14):
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c?h=v5.14#n2015
>
> > Signed-off-by: Tudor Cornea <tudor.cornea@gmail.com>
> >
> > ---
> > v2:
> > * Change title
> > * Remove max_rx_pkt_len fix in ixgbe_ethdev.c
> >    It's already fixed as part of Ferruh's changes in next-net branch,
> >    so this part should be redundant, now
> > ---
> >   drivers/net/ixgbe/ixgbe_rxtx.c | 4 +---
> >   1 file changed, 1 insertion(+), 3 deletions(-)
> >
> > diff --git a/drivers/net/ixgbe/ixgbe_rxtx.c
> b/drivers/net/ixgbe/ixgbe_rxtx.c
> > index b263dfe..a51450f 100644
> > --- a/drivers/net/ixgbe/ixgbe_rxtx.c
> > +++ b/drivers/net/ixgbe/ixgbe_rxtx.c
> > @@ -5673,11 +5673,9 @@ ixgbevf_dev_rx_init(struct rte_eth_dev *dev)
> >        * ixgbevf_rlpml_set_vf even if jumbo frames are not used. This
> way,
> >        * VF packets received can work in all cases.
> >        */
> > -     if (ixgbevf_rlpml_set_vf(hw, frame_size) != 0) {
> > +     if (ixgbevf_rlpml_set_vf(hw, frame_size) != 0)
> >               PMD_INIT_LOG(ERR, "Set max packet length to %d failed.",
> >                            frame_size);
> > -             return -EINVAL;
> > -     }
> >
> >       /*
> >        * Assume no header split and no VLAN strip support
> >
>
>
Hi Ferruh,

Thanks a lot for the good observations and for pointing me in the right
direction !

Tudor