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Date: Mon, 1 Sep 2014 16:30:38 +0200
From: Greg Kurz <gkurz@linux.vnet.ibm.com>
Message-ID: <20140901163038.4c30e526@bahia.local>
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Subject: Re: [Qemu-devel] qcow2, lazy_refcounts and killing qemu
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To: "Richard W.M. Jones" <rjones@redhat.com>
Cc: kwolf@redhat.com, qemu-devel@nongnu.org

On Mon, 1 Sep 2014 15:19:28 +0100
"Richard W.M. Jones" <rjones@redhat.com> wrote:

> A test case, attached.
> 
> Note that you have to look at the output of the final qemu-img info
> command.  In the case where it goes wrong, the 'backing file:' and
> 'backing file format:' lines disappear completely.  In the case where
> the bug is not reproduced, these lines are still present.
> 
> It's 100% reproducible for me when lazy_refcounts=on, and 0%
> reproducible when lazy_refcounts=off.
> 
> BUT it only occurs if the backing file is a remote source (nbd:... in
> this case), not if the backing file is a plain file.  Make of that
> what you will.
> 
> Rich.
> 

Thanks. I'll try that.

-- 
Gregory Kurz                                     kurzgreg@fr.ibm.com
                                                 gkurz@linux.vnet.ibm.com
Software Engineer @ IBM/Meiosys                  http://www.ibm.com
Tel +33 (0)562 165 496

"Anarchy is about taking complete responsibility for yourself."
        Alan Moore.