> -----Original Message-----
> From: Jesper Dangaard Brouer <bro...@redhat.com>
> Sent: Sunday, March 24, 2019 8:29 PM
> To: Ioana Ciocoi Radulescu <ruxandra.radule...@nxp.com>
> Cc: netdev@vger.kernel.org; da...@davemloft.net; Ioana Ciornei
> <ioana.cior...@nxp.com>; bro...@redhat.com
> Subject: Re: [PATCH net] dpaa2-eth: Fix possible access beyond end of array
>
> On Wed, 20 Mar 2019 14:11:04 +0000
> Ioana Ciocoi Radulescu <ruxandra.radule...@nxp.com> wrote:
>
> > Make sure we don't try to enqueue XDP_REDIRECT frames to an
> > inexistent FQ.
> >
> > While it is guaranteed not to have more than one queue per core,
> > having fewer queues than CPUs on an interface is a valid
> > configuration.
> >
> > Fixes: d678be1dc1ec ("dpaa2-eth: add XDP_REDIRECT support")
> > Reported-by: Jesper Dangaard Brouer <bro...@redhat.com>
> > Signed-off-by: Ioana Radulescu <ruxandra.radule...@nxp.com>
> > ---
> > drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> > index 2ba49e9..1a68052 100644
> > --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> > +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
> > @@ -1817,7 +1817,7 @@ static int dpaa2_eth_xdp_xmit_frame(struct
> net_device *net_dev,
> > dpaa2_fd_set_format(&fd, dpaa2_fd_single);
> > dpaa2_fd_set_ctrl(&fd, FD_CTRL_PTA);
> >
> > - fq = &priv->fq[smp_processor_id()];
> > + fq = &priv->fq[smp_processor_id() % dpaa2_eth_queue_count(priv)];
> > for (i = 0; i < DPAA2_ETH_ENQUEUE_RETRIES; i++) {
> > err = priv->enqueue(priv, fq, &fd, 0);
>
> Are you sure this is correct?
> How do you guard/lock concurrent CPUs from accessing 'fq' ?
We only use 'fq' in the enqueue command to hardware.
Our hardware can handle concurrent enqueue commands, we
might at most get a busy response from it.
Thanks,
Ioana
