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From: David Miller <davem@davemloft.net>
Subject: Re: kernel panic in skb_copy_bits
Date: Thu, 04 Jul 2013 14:32:46 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 04 Jul 2013 03:12:10 -0700

> It looks like a typical COW issue to me.

Generically speaking, if we have to mess with page protections this
eliminates the performance gain from bypass/zerocopy/whatever that
these virtualization layers are doing.

But there may be other factors involved which might mitigate that.