From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andriy Berestovskyy <Andriy.Berestovskyy@caviumnetworks.com>
Subject: Re: [PATCH v2] ether: use a default for max Rx frame
 size in configure()
Date: Mon, 27 Mar 2017 10:38:13 +0200
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To: "Yang, Qiming" <qiming.yang@intel.com>,
 Thomas Monjalon <thomas.monjalon@6wind.com>
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Hey Qiming,

On 27.03.2017 08:15, Yang, Qiming wrote:
> I don't think this is a bug. Return errors when configure an invalid max_rx_pkt_len is suitable for this generic API.

It is not a bug, it is an inconsistency. At the moment we can set 
max_rx_pkt_len for normal frames and if it is out of range a default 
value will be used instead.

IMO we should expect the same behavior from the same function for the 
jumbo frames.

So at the moment we have:
jumbo == 0, max_rx_pkt_len == 0, result: max_rx_pkt_len = ETHER_MAX_LEN
jumbo == 0, max_rx_pkt_len == 1200, result: max_rx_pkt_len = 1200
jumbo == 1, max_rx_pkt_len == 0, result: error
jumbo == 1, max_rx_pkt_len == 9K, result: error or max_rx_pkt_len = 9K


> It's not suitable to give a default value in this function.

We use a default value for normal frames at the moment. The comment:

uint32_t max_rx_pkt_len;  /**< Only used if jumbo_frame enabled. */

is obsolete and in fact we use max_rx_pkt_len both for jumbo and normal 
frames. So the patch clarifies this as well.


Regards,
Andriy