From mboxrd@z Thu Jan 1 00:00:00 1970 From: sfeldma@gmail.com Subject: [PATCH net-next] rocker: move netevent neigh update to processes context Date: Wed, 20 May 2015 22:05:07 -0700 Message-ID: <1432184707-27252-1-git-send-email-sfeldma@gmail.com> Cc: jiri@resnulli.us, simon.horman@netronome.com, makita.toshiaki@lab.ntt.co.jp To: netdev@vger.kernel.org Return-path: Received: from mail-pd0-f182.google.com ([209.85.192.182]:36628 "EHLO mail-pd0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751186AbbEUFDu (ORCPT ); Thu, 21 May 2015 01:03:50 -0400 Received: by pdfh10 with SMTP id h10so94693146pdf.3 for ; Wed, 20 May 2015 22:03:50 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: From: Scott Feldman In review of Simon's patchset "rocker: transaction fixes". it was noted that rocker->neigh_tbl_next_index was unprotected in the call path below and could race with other contexts calling rocker_port_ipv4_neigh(): arp_process() neigh_update() rocker_neigh_update() rocker_port_ipv4_neigh() To fix, move the neigh_update() event processing to process contexts and hold rtnl_lock to call rocker_port_ipv4_neigh(). This will protect rocker->neigh_tbl_next_index accesses and is more consistent with the rest of the driver code where non-I/O processing is done under process context with rtnl_lock held. Signed-off-by: Scott Feldman --- drivers/net/ethernet/rocker/rocker.c | 52 +++++++++++++++++++++++++++++----- 1 file changed, 45 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/rocker/rocker.c b/drivers/net/ethernet/rocker/rocker.c index 0f5e962..4cff2f6 100644 --- a/drivers/net/ethernet/rocker/rocker.c +++ b/drivers/net/ethernet/rocker/rocker.c @@ -5240,14 +5240,52 @@ static struct notifier_block rocker_netdevice_nb __read_mostly = { * Net event notifier event handler ************************************/ -static int rocker_neigh_update(struct net_device *dev, struct neighbour *n) +struct rocker_neigh_update_work { + struct work_struct work; + struct rocker_port *rocker_port; + int flags; + __be32 ip_addr; + unsigned char ha[ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))]; +}; + +static void rocker_event_neigh_update_work(struct work_struct *work) { - struct rocker_port *rocker_port = netdev_priv(dev); - int flags = (n->nud_state & NUD_VALID) ? 0 : ROCKER_OP_FLAG_REMOVE; - __be32 ip_addr = *(__be32 *)n->primary_key; + struct rocker_neigh_update_work *nw = + container_of(work, struct rocker_neigh_update_work, work); + int err; + + rtnl_lock(); + err = rocker_port_ipv4_neigh(nw->rocker_port, SWITCHDEV_TRANS_NONE, + nw->flags, nw->ip_addr, nw->ha); + rtnl_unlock(); + + if (err) + netdev_warn(nw->rocker_port->dev, + "failed to handle neigh %pI4 update (err %d)\n", + &nw->ip_addr, err); - return rocker_port_ipv4_neigh(rocker_port, SWITCHDEV_TRANS_NONE, - flags, ip_addr, n->ha); + kfree(work); +} + +static int rocker_event_neigh_update(struct net_device *dev, + struct neighbour *n) +{ + struct rocker_neigh_update_work *nw; + + nw = kmalloc(sizeof(*nw), GFP_ATOMIC); + if (!nw) + return -ENOMEM; + + INIT_WORK(&nw->work, rocker_event_neigh_update_work); + + nw->rocker_port = netdev_priv(dev); + nw->flags = (n->nud_state & NUD_VALID) ? 0 : ROCKER_OP_FLAG_REMOVE; + nw->ip_addr = *(__be32 *)n->primary_key; + memcpy(nw->ha, n->ha, sizeof(nw->ha)); + + schedule_work(&nw->work); + + return 0; } static int rocker_netevent_event(struct notifier_block *unused, @@ -5264,7 +5302,7 @@ static int rocker_netevent_event(struct notifier_block *unused, dev = n->dev; if (!rocker_port_dev_check(dev)) return NOTIFY_DONE; - err = rocker_neigh_update(dev, n); + err = rocker_event_neigh_update(dev, n); if (err) netdev_warn(dev, "failed to handle neigh update (err %d)\n", -- 1.7.10.4