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Date: Tue, 28 Jul 2009 09:59:23 +0300
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Subject: [Qemu-devel] Re: [PATCH] RFC: use logging count for individual
	regions
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To: Jan Kiszka <jan.kiszka@web.de>
Cc: Glauber Costa <glommer@redhat.com>, qemu-devel@nongnu.org, aliguori@us.ibm.com

On 07/28/2009 09:50 AM, Jan Kiszka wrote:
>
>    
>> Unlike the qemu dirty byte-map, the kvm dirty log can only service one
>> user.  As we have multiple users (vga and migration), we need some way
>> to fix this impedance mismatch.  I think refcounts are the easiest.
>>      
>
> This case is already handled upstream. If we had more users, we would
> need refcounts.
>    

If we turn off logging on migration failure, then we'd introduce a bug 
in vga logging, no?

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.