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From: "Laurent Lagrange" <lagrange@fr.oleane.com>
To: <linuxppc-embedded@ozlabs.org>
Date: Fri, 28 Jan 2005 15:29:48 +0100
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Subject: 8021q and change_mtu problem
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Hello,

I have tried to use the "change_mtu" function with a 8021q network device.
I have compare this function with an other one define for ethernet devices
in /drivers/net/net_init.c.

These functions always return -EINVAL when the new mtu value is invalid.
But for a valid mtu value the first one returns the new value and the second
one returns 0.

I use a linux 2.6.9 kernel from kernel.org.

I have tried this very simple patch and the function works fine.

--- net/8021q/vlan_dev.c    Fri Jan 28 15:07:58 2005
+++ net/8021q/vlan_dev.c  Fri Jan 28 15:12:12 2005
@@ -527,7 +527,7 @@

    dev->mtu = new_mtu;

-   return new_mtu;
+   return 0;

Laurent