Date: Tue, 17 May 2011 09:21:11 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Shirley Ma <mashirle@us.ibm.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>,
        David Miller <davem@davemloft.net>,
        Eric Dumazet <eric.dumazet@gmail.com>, Avi Kivity <avi@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>, netdev@vger.kernel.org,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH V5 2/6 net-next] netdevice.h: Add zero-copy flag in
 netdevice
Message-ID: <20110517062111.GD26989@redhat.com>
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On Mon, May 16, 2011 at 04:32:18PM -0700, Shirley Ma wrote:
> Hello Michael,
> 
> Looks like to use a new flag requires more time/work.
> I am thinking
> whether we can just use HIGHDMA flag to enable zero-copy in macvtap to
> avoid the new flag for now since mavctap uses real NICs as lower device?
> 
> Thanks
> Shirley

Problem is, in your patch there are a set of restrictions on what the
device can do with the skb that we need to enforce somehow.
Also, how do we know it's a 'real NIC' and not a software device?

-- 
MST
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