From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH net-next RFC 6/8] net: make gro configurable
Date: Fri, 14 Sep 2018 11:38:48 -0700
Message-ID: <20180914113848.14b931df@xeon-e3>
References: <20180914175941.213950-1-willemdebruijn.kernel@gmail.com>
        <20180914175941.213950-7-willemdebruijn.kernel@gmail.com>
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Cc: netdev@vger.kernel.org, pabeni@redhat.com,
        steffen.klassert@secunet.com, davem@davemloft.net,
        Willem de Bruijn <willemb@google.com>
To: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
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On Fri, 14 Sep 2018 13:59:39 -0400
Willem de Bruijn <willemdebruijn.kernel@gmail.com> wrote:

> diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
> index e5d236595206..8cb8e02c8ab6 100644
> --- a/drivers/net/vxlan.c
> +++ b/drivers/net/vxlan.c
> @@ -572,6 +572,7 @@ static struct sk_buff *vxlan_gro_receive(struct sock *sk,
>  					 struct list_head *head,
>  					 struct sk_buff *skb)
>  {
> +	const struct net_offload *ops;
>  	struct sk_buff *pp = NULL;
>  	struct sk_buff *p;
>  	struct vxlanhdr *vh, *vh2;
> @@ -606,6 +607,12 @@ static struct sk_buff *vxlan_gro_receive(struct sock *sk,
>  			goto out;
>  	}
>  
> +	rcu_read_lock();
> +	ops = net_gro_receive(dev_offloads, ETH_P_TEB);
> +	rcu_read_unlock();
> +	if (!ops)
> +		goto out;

Isn't rcu_read_lock already held here?
RCU read lock is always held in the receive handler path

> +
>  	skb_gro_pull(skb, sizeof(struct vxlanhdr)); /* pull vxlan header */
>  
>  	list_for_each_entry(p, head, list) {
> @@ -621,6 +628,7 @@ static struct sk_buff *vxlan_gro_receive(struct sock *sk,
>  	}
>  
>  	pp = call_gro_receive(eth_gro_receive, head, skb);
> +
>  	flush = 0;

whitespace change crept into this patch.