Hi, Is it being called after device start? If yes, then *dev_mtu_set() will not serve the purpose as this function expects the device to be stopped first.
Regards, Nitin -----Original Message----- From: Stokes, Ian [mailto:[email protected]] Sent: Friday, November 24, 2017 1:57 PM To: Matteo Croce <[email protected]>; [email protected]; Kavanagh, Mark B <[email protected]> Subject: Re: [ovs-dev] [PATCH] netdev-dpdk: defer MTU set after interface start > Some PMD assumes that the RX buffers are already allocated when > setting the device MTU, because the RX buffer size depends on the MTU. > This worked until 67fe6d635193 added a call to rte_eth_dev_set_mtu() > in the init code, which would set the MTU before the RX buffer > allocation, triggering a segmentation fault with some PMD: > > Stack trace of thread 20680: > #0 0x0000559464396534 qede_set_mtu (ovs-vswitchd) > #1 0x0000559464323c41 rte_eth_dev_set_mtu (ovs-vswitchd) > #2 0x00005594645f5e85 dpdk_eth_dev_queue_setup (ovs-vswitchd) > #3 0x00005594645f8ae6 netdev_dpdk_reconfigure (ovs-vswitchd) > #4 0x000055946452225c reconfigure_datapath (ovs-vswitchd) > #5 0x0000559464522d07 do_add_port (ovs-vswitchd) > #6 0x0000559464522e8d dpif_netdev_port_add (ovs-vswitchd) > #7 0x0000559464528dde dpif_port_add (ovs-vswitchd) > #8 0x00005594644dc0e0 port_add (ovs-vswitchd) > #9 0x00005594644d2ab1 ofproto_port_add (ovs-vswitchd) > #10 0x00005594644c0a85 bridge_add_ports__ (ovs-vswitchd) > #11 0x00005594644c26e8 bridge_reconfigure (ovs-vswitchd) > #12 0x00005594644c5c49 bridge_run (ovs-vswitchd) > #13 0x00005594642d4155 main (ovs-vswitchd) > #14 0x00007f0e1444bc05 __libc_start_main (libc.so.6) > #15 0x00005594642d8328 _start (ovs-vswitchd) > > A possible solution could be to move the first call to > rte_eth_dev_set_mtu() just after the device start instead of > dpdk_eth_dev_queue_setup() which, by the way, set the MTU multiple > times as the call to rte_eth_dev_set_mtu() was in a loop. > > CC: Mark Kavanagh <[email protected]> > Fixes: 67fe6d635193 ("netdev-dpdk: use rte_eth_dev_set_mtu.") > Signed-off-by: Matteo Croce <[email protected]> > --- > lib/netdev-dpdk.c | 14 +++++++------- > 1 file changed, 7 insertions(+), 7 deletions(-) > > diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c index > 76e79be25..229aa4a76 100644 > --- a/lib/netdev-dpdk.c > +++ b/lib/netdev-dpdk.c > @@ -750,13 +750,6 @@ dpdk_eth_dev_queue_setup(struct netdev_dpdk *dev, > int n_rxq, int n_txq) > break; > } > > - diag = rte_eth_dev_set_mtu(dev->port_id, dev->mtu); > - if (diag) { > - VLOG_ERR("Interface %s MTU (%d) setup error: %s", > - dev->up.name, dev->mtu, rte_strerror(-diag)); > - break; > - } > - > for (i = 0; i < n_txq; i++) { > diag = rte_eth_tx_queue_setup(dev->port_id, i, dev->txq_size, > dev->socket_id, NULL); @@ - > 849,6 +842,13 @@ dpdk_eth_dev_init(struct netdev_dpdk *dev) > return -diag; > } > > + diag = rte_eth_dev_set_mtu(dev->port_id, dev->mtu); > + if (diag) { > + VLOG_ERR("Interface %s MTU (%d) setup error: %s", > + dev->up.name, dev->mtu, rte_strerror(-diag)); > + return -diag; > + } > + In my testing I didn't see any issues here, but would like to flag it to our MTU Guru (Mark K). Any opinion on this? From the API description it looks like it is ok? > rte_eth_promiscuous_enable(dev->port_id); > rte_eth_allmulticast_enable(dev->port_id); > > -- > 2.13.6 > > _______________________________________________ > dev mailing list > [email protected] > https://mail.openvswitch.org/mailman/listinfo/ovs-dev _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
