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Date: Mon, 30 Jun 2008 20:43:17 +0200
From: Patrick McHardy <kaber@trash.net>
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To: Ben Greear <greearb@candelatech.com>
CC: Pavlin Radoslavov <pavlin@ICSI.Berkeley.EDU>, xorp-hackers@xorp.org
Subject: Re: Linux VLAN config if interface is down
References: <200806301834.m5UIYQjb023376@fruitcake.ICSI.Berkeley.EDU>
	<48692871.4060909@candelatech.com>
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Ben Greear wrote:
> Pavlin Radoslavov wrote:
>> [Note: this is not exactly XORP-specific question, but it affects
>> the XORP FEA]
>>
>> Ben,
>>
>> I have a Linux VLAN-related question which hopefully you can answer,
>> because I believe you were the primary author of the VLAN code
>> in the Linux kernel.
>
> I did most of the original work, but Patrick is now the maintainer
> and knows the code better.
>
> I would like to see this constraint you mention removed as well.
> From what I recall, the main problem is that some HW-Accel drivers
> might not handle adding vlans properly while the NIC is disabled.

I've planned to look into this inconsisteny once I've fixed
the other inconsistencies related to HW accel and packet
sockets, but so far I didn't find enough time to finish this.
Something like 2.6.28 sounds realistic.

 From a quick look at a few drivers with VLAN accel support
it seems they would handle this fine, so if someone really
needs a short term fix, I'd suggest to simply remove that
check from the VLAN code.
]