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Date: Tue, 12 Oct 2010 10:22:32 -0500
From: Anthony Liguori <aliguori@linux.vnet.ibm.com>
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Subject: [Qemu-devel] Re: [PATCH v2 6/7] qed: Read/write support
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To: Kevin Wolf <kwolf@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>, Avi Kivity <avi@redhat.com>, Christoph Hellwig <hch@lst.de>, Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>, qemu-devel@nongnu.org

On 10/12/2010 10:08 AM, Kevin Wolf wrote:
>   Otherwise we might destroy data that isn't
> even touched by the guest request in case of a crash.
>    

The failure scenarios are either that the cluster is leaked in which 
case, the old version of the data is still present or the cluster is 
orphaned because the L2 entry is written, in which case the old version 
of the data is present.

Are you referring to a scenario where the cluster is partially written 
because the data is present in the write cache and the write cache isn't 
flushed on power failure?

Regards,

Anthony Liguori

> Kevin
>