From: "Richard W.M. Jones" <rjones@redhat.com>
To: Greg Kurz <gkurz@linux.vnet.ibm.com>
Cc: kwolf@redhat.com, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] qcow2, lazy_refcounts and killing qemu
Date: Mon, 1 Sep 2014 15:19:28 +0100 [thread overview]
Message-ID: <20140901141928.GW1302@redhat.com> (raw)
In-Reply-To: <20140901144102.0aaae712@bahia.local>
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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.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-top is 'top' for virtual machines. Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top
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next prev parent reply other threads:[~2014-09-01 14:19 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-30 14:53 [Qemu-devel] qcow2, lazy_refcounts and killing qemu Richard W.M. Jones
2014-09-01 12:41 ` Greg Kurz
2014-09-01 13:07 ` Richard W.M. Jones
2014-09-01 14:19 ` Richard W.M. Jones [this message]
2014-09-01 14:23 ` Richard W.M. Jones
2014-09-01 14:30 ` Greg Kurz
2014-09-05 15:39 ` Stefan Hajnoczi
2014-09-05 17:41 ` Richard W.M. Jones
2014-09-08 7:16 ` Markus Armbruster
2014-09-08 18:29 ` Max Reitz
2014-09-08 9:57 ` Stefan Hajnoczi
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