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Date: Mon, 15 Nov 2010 15:05:39 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] Re: [PATCHv2 2/2] tap: mark fd handler as device
References: <20101104180406.GA2820@redhat.com>	<5f91d600c749e66de107f60298c5ebd36645beff.1288892774.git.mst@redhat.com>	<m3oc9qr649.fsf@trasno.org>	<4CE149CB.1040301@codemonkey.ws>	<20101115151817.GA30509@redhat.com>	<4CE15B39.5070207@codemonkey.ws>
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To: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Juan Quintela <quintela@redhat.com>, qemu-devel@nongnu.org, "Michael S. Tsirkin" <mst@redhat.com>

On 11/15/2010 02:53 PM, Stefan Hajnoczi wrote:
>
> vhost has a solution for this: register a VMChangeStateHandler
> function that stops ioeventfd while vm_stop(0) is in effect.  Then
> poll to see if there is work pending.
>
> I will add equivalent functionality to virtio-ioeventfd.
>    

I still think that stopping this at the net/block layer is going to be a 
lot more robust in the long term.  All net/block traffic flows through a 
single set of interfaces whereas getting the devices to completely stop 
themselves requires touching every device and making sure that noone 
adds back vmstop-unfriendly behavior down the road.

Regards,

Anthony Liguori

> Stefan
>