Re: [dpdk-stable] [PATCH 1/2] net/mlx5: fix return value of start operation

[Olivier Matz <olivier.matz@6wind.com>]

On Thu, Jan 18, 2018 at 05:04:27PM +0100, Nélio Laranjeiro wrote:
> On Thu, Jan 18, 2018 at 02:00:42PM +0100, Olivier Matz wrote:
> > On error, mlx5_dev_start() does not return a negative value
> > as it is supposed to do. The consequence is that the application
> > (ex: testpmd) does not notice that the port is not started
> > and begins the rxtx on an uninitialized port, which crashes.
> > 
> > Fixes: e1016cb73383 ("net/mlx5: fix Rx interrupts management")
> > Cc: stable@dpdk.org
> > 
> > Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
> > ---
> >  drivers/net/mlx5/mlx5_trigger.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/mlx5/mlx5_trigger.c b/drivers/net/mlx5/mlx5_trigger.c
> > index 1a20967a2..44f702daa 100644
> > --- a/drivers/net/mlx5/mlx5_trigger.c
> > +++ b/drivers/net/mlx5/mlx5_trigger.c
> > @@ -166,6 +166,7 @@ mlx5_dev_start(struct rte_eth_dev *dev)
> >  		ERROR("%p: an error occurred while configuring control flows:"
> >  		      " %s",
> >  		      (void *)priv, strerror(err));
> > +		err = -err;
> >  		goto error;
> >  	}
> >  	err = priv_flow_start(priv, &priv->flows);
> > @@ -173,6 +174,7 @@ mlx5_dev_start(struct rte_eth_dev *dev)
> >  		ERROR("%p: an error occurred while configuring flows:"
> >  		      " %s",
> >  		      (void *)priv, strerror(err));
> > +		err = -err;
> >  		goto error;
> >  	}
> >  	err = priv_rx_intr_vec_enable(priv);
> > @@ -196,7 +198,7 @@ mlx5_dev_start(struct rte_eth_dev *dev)
> >  	priv_rxq_stop(priv);
> >  	priv_flow_delete_drop_queue(priv);
> >  	priv_unlock(priv);
> > -	return -err;
> > +	return err;
> >  }
> >  
> >  /**
> 
> err in the function is handled with positives errno's, adding only those
> two and returning err will make the other positive.

I tried to check the return value of all functions called by mlx5_dev_start()
(negative or positive). Do you see something wrong?