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Date: Mon, 08 Mar 2010 11:52:13 +0200
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] Inter-VM shared memory PCI device
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	<201003072254.00040.paul@codesourcery.com>
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To: Paul Brook <paul@codesourcery.com>
Cc: Cam Macdonell <cam@cs.ualberta.ca>, qemu-devel@nongnu.org, kvm@vger.kernel.org

On 03/08/2010 12:53 AM, Paul Brook wrote:
>> Support an inter-vm shared memory device that maps a shared-memory object
>> as a PCI device in the guest.  This patch also supports interrupts between
>> guest by communicating over a unix domain socket.  This patch applies to
>>   the qemu-kvm repository.
>>      
> No. All new devices should be fully qdev based.
>
> I suspect you've also ignored a load of coherency issues, especially when not
> using KVM. As soon as you have shared memory in more than one host
> thread/process you have to worry about memory barriers.
>    

Shouldn't it be sufficient to require the guest to issue barriers (and 
to ensure tcg honours the barriers, if someone wants this with tcg)?.

-- 
error compiling committee.c: too many arguments to function