From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jiri Pirko <jiri@resnulli.us>
Subject: Re: [patch net 0/2] mlxsw: Couple of fixes
Date: Wed, 5 Oct 2016 13:14:51 +0200
Message-ID: <20161005111451.GB2293@nanopsycho>
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 <20161004.202927.1650578832896717724.davem@davemloft.net>
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Wed, Oct 05, 2016 at 02:29:27AM CEST, davem@davemloft.net wrote:
>From: Jiri Pirko <jiri@resnulli.us>
>Date: Tue,  4 Oct 2016 09:46:03 +0200
>
>> Couple of fixes from Yotam.
>
>Series applied, thanks.
>
>Note that needed_headroom is a request, rather than a guarantee, so you
>may in some rare cases need to realloc your headroom if the kernel was
>not able to meet your request.

We already do that: 

        if (unlikely(skb_headroom(skb) < MLXSW_TXHDR_LEN)) {
                struct sk_buff *skb_orig = skb;

                skb = skb_realloc_headroom(skb, MLXSW_TXHDR_LEN);
                if (!skb) {
                        this_cpu_inc(mlxsw_sp_port->pcpu_stats->tx_dropped);
                        dev_kfree_skb_any(skb_orig);
                        return NETDEV_TX_OK;
                }
        }