Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
To:     "David S. Miller" <davem@davemloft.net>
Cc:     William Tu <u9012063@gmail.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Subject: [PATCH] ip6erspan: remove the incorrect mtu limit for ip6erspan
Date:   Tue,  8 Oct 2019 17:56:03 +0800
Message-Id: <1570528563-8062-1-git-send-email-yanhaishuang@cmss.chinamobile.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

ip6erspan driver calls ether_setup(), after commit 61e84623ace3
("net: centralize net_device min/max MTU checking"), the range
of mtu is [min_mtu, max_mtu], which is [68, 1500] by default.

It causes the dev mtu of the erspan device to not be greater
than 1500, this limit value is not correct for ip6erspan tap
device.

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
---
 net/ipv6/ip6_gre.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index d5779d6..787d9f2 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -2192,6 +2192,7 @@ static void ip6erspan_tap_setup(struct net_device *dev)
 {
 	ether_setup(dev);
 
+	dev->max_mtu = 0;
 	dev->netdev_ops = &ip6erspan_netdev_ops;
 	dev->needs_free_netdev = true;
 	dev->priv_destructor = ip6gre_dev_free;
-- 
1.8.3.1