From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rick Jones <rick.jones2@hpe.com>
Subject: Re: [PATCH net-next 2/4] mlx4: xdp: Allow raising MTU up to one page
 minus eth and vlan hdrs
Date: Fri, 2 Dec 2016 16:07:09 -0800
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Cc: Alexei Starovoitov <ast@fb.com>,
        Brenden Blanco <bblanco@plumgrid.com>,
        Daniel Borkmann <daniel@iogearbox.net>,
        David Miller <davem@davemloft.net>,
        Saeed Mahameed <saeedm@mellanox.com>,
        Tariq Toukan <tariqt@mellanox.com>,
        Kernel Team <kernel-team@fb.com>
To: Martin KaFai Lau <kafai@fb.com>, netdev@vger.kernel.org
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On 12/02/2016 03:23 PM, Martin KaFai Lau wrote:
> When XDP prog is attached, it is currently limiting
> MTU to be FRAG_SZ0 - ETH_HLEN - (2 * VLAN_HLEN) which is 1514
> in x86.
>
> AFAICT, since mlx4 is doing one page per packet for XDP,
> we can at least raise the MTU limitation up to
> PAGE_SIZE - ETH_HLEN - (2 * VLAN_HLEN) which this patch is
> doing.  It will be useful in the next patch which allows
> XDP program to extend the packet by adding new header(s).

Is mlx4 the only driver doing page-per-packet?

rick jones