Re: [dpdk-dev] [PATCH] ixgbe: fix segmentation fault when start secondary process

[Bruce Richardson <bruce.richardson@intel.com>]

On Thu, Dec 18, 2014 at 10:22:28AM +0000, Qiu, Michael wrote:
> On 12/18/2014 6:17 PM, Qiu, Michael wrote:
> > EAL:   probe driver: 8086:10fb rte_ixgbe_pmd
> > EAL:   PCI memory mapped at 0x7f18c2a00000
> > EAL:   PCI memory mapped at 0x7f18c2a80000
> > Segmentation fault (core dumped)
> >
> > This is introduced by commit: 46bc9d75
> > 	ixgbe: fix multi-process support
> > When start primary process with command line:
> > ./app/test/test -n 1 -c ffff -m 64
> > then start the second one:
> > ./app/test/test -n 1 --proc-type=secondary --file-prefix=rte
> > This segment-fault will occur.
> >
> > Root cause is test app on primary process only starts device, but
> > the queue need initialized by manually command line.
> > So the tx queue is still NULL when secondary process startup.
> >
> > Reported-by: Yong Liu <yong.liu@intel.com>
> > Signed-off-by: Michael Qiu <michael.qiu@intel.com>
> > ---
> >  lib/librte_pmd_ixgbe/ixgbe_ethdev.c | 16 +++++++++++++---
> >  1 file changed, 13 insertions(+), 3 deletions(-)
> >
> > diff --git a/lib/librte_pmd_ixgbe/ixgbe_ethdev.c b/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
> > index 9401916..87ed6ee 100644
> > --- a/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
> > +++ b/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
> > @@ -749,9 +749,19 @@ eth_ixgbe_dev_init(__attribute__((unused)) struct eth_driver *eth_drv,
> >  	 */
> >  	if (rte_eal_process_type() != RTE_PROC_PRIMARY){
> >  		struct igb_tx_queue *txq;
> > -		/* TX queue function in primary, set by last queue initialized */
> > -		txq = eth_dev->data->tx_queues[eth_dev->data->nb_tx_queues-1];
> > -		set_tx_function(eth_dev, txq);
> > +		/* TX queue function in primary, set by last queue initialized
> > +		 * Tx queue may not initialized by primary process
> > +		 * */
> > +		if (eth_dev->data->tx_queues) {
> > +			txq = eth_dev->data->tx_queues[eth_dev->data->nb_tx_queues-1];
> > +			set_tx_function(eth_dev, txq);
> > +		} else {
> > +			/* Shall we exit this process if we get here? */
> 
> I'm just not sure if it is better to terminated when Tx queues are NULL
> in secondary process.
> 
> Thanks
> Michael

No, don't terminate. Printing a message is enough.


> > +			PMD_INIT_LOG(INFO, "Last tx queue initialized fail in "
> > +				     "secondary process, please verify if tx "
> > +				     "queues were initialized in primary "
> > +				     "process!\n");
> > +		}

Maybe shorten message to: "No TX queues configured yet. Using default TX function."

> >  
> >  		if (eth_dev->data->scattered_rx)
> >  			eth_dev->rx_pkt_burst = ixgbe_recv_scattered_pkts;
> 
>