From: Jakub Kicinski Date: Sun, 3 Sep 2017 01:26:05 +0000 (-0700) Subject: nfp: flower: restore RTNL locking around representor updates X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=9ce4fa548313f585c637aa846f7fc904b676bf43;p=openwrt%2Fstaging%2Fblogic.git nfp: flower: restore RTNL locking around representor updates When we moved to updating representors from a workqueue grabbing the RTNL somehow got lost in the process. Restore it, and make sure RCU lock is not held while we are grabbing the RTNL. RCU protects the representor table, so since we will be under RTNL we can drop RCU lock as soon as we find the netdev pointer. RTNL is needed for the dev_set_mtu() call. Fixes: 2dff19622421 ("nfp: process MTU updates from firmware flower app") Signed-off-by: Jakub Kicinski Reviewed-by: Simon Horman Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/netronome/nfp/flower/cmsg.c b/drivers/net/ethernet/netronome/nfp/flower/cmsg.c index e014d862b9b6..c3ca05d10fe1 100644 --- a/drivers/net/ethernet/netronome/nfp/flower/cmsg.c +++ b/drivers/net/ethernet/netronome/nfp/flower/cmsg.c @@ -141,12 +141,14 @@ nfp_flower_cmsg_portmod_rx(struct nfp_app *app, struct sk_buff *skb) msg = nfp_flower_cmsg_get_data(skb); link = msg->info & NFP_FLOWER_CMSG_PORTMOD_INFO_LINK; + rtnl_lock(); rcu_read_lock(); netdev = nfp_app_repr_get(app, be32_to_cpu(msg->portnum)); + rcu_read_unlock(); if (!netdev) { nfp_flower_cmsg_warn(app, "ctrl msg for unknown port 0x%08x\n", be32_to_cpu(msg->portnum)); - rcu_read_unlock(); + rtnl_unlock(); return; } @@ -161,7 +163,7 @@ nfp_flower_cmsg_portmod_rx(struct nfp_app *app, struct sk_buff *skb) } else { netif_carrier_off(netdev); } - rcu_read_unlock(); + rtnl_unlock(); } static void