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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Yunsheng Lin' <linyunsheng@huawei.com>,
        "davem@davemloft.net" <davem@davemloft.net>
CC:     "dsahern@gmail.com" <dsahern@gmail.com>,
        "jiri@mellanox.com" <jiri@mellanox.com>,
        "allison@lohutok.net" <allison@lohutok.net>,
        "mmanning@vyatta.att-mail.com" <mmanning@vyatta.att-mail.com>,
        "petrm@mellanox.com" <petrm@mellanox.com>,
        "dcaratti@redhat.com" <dcaratti@redhat.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH RFC] net: vlan: reverse 4 bytes of vlan header when
 setting initial MTU
Thread-Topic: [PATCH RFC] net: vlan: reverse 4 bytes of vlan header when
 setting initial MTU
Thread-Index: AQHViAshdgiBu05N4kSdJcAPfvn0KKdlLGIQ
Date:   Mon, 21 Oct 2019 14:46:20 +0000
Message-ID: <8f07f4aad98e44358b92e1e340df131f@AcuMS.aculab.com>
References: <1571660763-117936-1-git-send-email-linyunsheng@huawei.com>
In-Reply-To: <1571660763-117936-1-git-send-email-linyunsheng@huawei.com>
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From: Yunsheng Lin
> Sent: 21 October 2019 13:26
> Currently the MTU of vlan netdevice is set to the same MTU
> of the lower device, which requires the underlying device
> to handle it as the comment has indicated:
> 
> 	/* need 4 bytes for extra VLAN header info,
> 	 * hope the underlying device can handle it.
> 	 */
> 	new_dev->mtu = real_dev->mtu;
> 
> Currently most of the physical netdevs seems to handle above
> by reversing 2 * VLAN_HLEN for L2 packet len.

s/reverse/reserve/g

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