On Wed, 15 Feb 2017 10:55:24 +0000
"Richard W.M. Jones" <rjones@xxxxxxxxxx> wrote:
> On Tue, Feb 14, 2017 at 10:03:54PM +0100, Tomáš Golembiovský wrote:
> > Hi,
> >
> > On Tue, 14 Feb 2017 15:58:45 +0000
> > "Richard W.M. Jones" <rjones@xxxxxxxxxx> wrote:
> >
> > > The patches compile.
> > >
> > > I looked at both commits and they at least superficially seem
> > > sensible. I'm not intimately familiar enough with the original code
> > > to review this fully.
> > >
> > > However I want to try to test this using libguestfs. I believe the
> > > following test case should be sufficient:
> > >
> > > $ cd /var/tmp
> > > $ truncate -s 1M backing.img
> > > $ qemu-img create \
> > > -b 'json:{"driver":"raw", "file":{"filename":"/var/tmp/backing.img"}}' \
> >
> > The problem lies in the JSON here. Libvirt lacks the driver probing
> > mechanism QEMU has (which makes sense). That means one has to be
> > explicit about the drivers. Try with the following backing definition:
> >
> > json:{"driver":"raw", "file":{ "driver":"file", "filename":"/var/tmp/backing.img"}}
>
> OK, that works. However it also works with the unpatched version of
> libvirt, so it's not proof that these patches fix any problem.
Ah, sorry. I didn't notice your JSON was bad from the start and I just
blindly extended it. The correct JSON should look like this:
json: {
"file": {
"driver":"raw",
"file": {
"driver":"file",
"filename":"/var/tmp/backing.img"
}
}
}
Tomas
>
> Rich.
>
> --
> Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
> Read my programming and virtualization blog: http://rwmj.wordpress.com
> virt-df lists disk usage of guests without needing to install any
> software inside the virtual machine. Supports Linux and Windows.
> http://people.redhat.com/~rjones/virt-df/
--
Tomáš Golembiovský <tgolembi@xxxxxxxxxx>
--
libvir-list mailing list
libvir-list@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/libvir-list
