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Date: Mon, 1 Sep 2014 14:07:00 +0100
From: "Richard W.M. Jones" <rjones@redhat.com>
Message-ID: <20140901130700.GV1302@redhat.com>
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Subject: Re: [Qemu-devel] qcow2, lazy_refcounts and killing qemu
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To: Greg Kurz <gkurz@linux.vnet.ibm.com>
Cc: kwolf@redhat.com, qemu-devel@nongnu.org

On Mon, Sep 01, 2014 at 02:41:02PM +0200, Greg Kurz wrote:
> On Sat, 30 Aug 2014 15:53:13 +0100
> "Richard W.M. Jones" <rjones@redhat.com> wrote:
> > I can reproduce this easily, although of course the reproducer will
> > involve libguestfs.
> > 
> > Rich.
> > 
> 
> Can you share this reproducer ?

The immediate reproducer (not very useful for you) is virt-v2v, if you
enable lazy_refcounts by hacking the call to qemu-img here:

https://github.com/libguestfs/libguestfs/blob/master/v2v/v2v.ml#L102

I'll try to come up with an actual reproducer, but I stress it's still
going to use libguestfs because that's the only sane way to run qemu
for the purposes of this test.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-p2v converts physical machines to virtual machines.  Boot with a
live CD or over the network (PXE) and turn machines into KVM guests.
http://libguestfs.org/virt-v2v