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From: "David S. Miller" <davem@davemloft.net>
Subject: Re: [PATCH]: was Re: LLTX and netif_stop_queue
Date: Wed, 26 Jan 2005 22:32:47 -0800
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To: Lennert Buytenhek <buytenh@wantstofly.org>
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On Wed, 26 Jan 2005 14:25:12 +0100
Lennert Buytenhek <buytenh@wantstofly.org> wrote:

> I've thought about this a bit, and the only sane way of doing recursion
> detection that doesn't involve 'struct net_device' would be to keep track
> of the recursion depth (perhaps per-CPU as you suggest) and tossing the
> packet when it exceeds some random value, right?

Yes, that's the idea.

> To reproduce the current behaviour more closely you'd have to keep a
> small per-CPU array of 'struct net_device *' pointers as a kind of
> recursion stack, and toss the packet when you hit a net_device that's
> already on the list.  But that seems like slight overkill.

Indeed.