[Pkg-libvirt-maintainers] Bug#843940: Bug#843940: libvirt-daemon: "Permission denied" errors in VMM/virt-manager when dynamic_ownership=0

[Guido Günther]

contral: reassign -1 virt-manager
control: severity -1 minor
control: tags -1 +moreifo

On Thu, Nov 10, 2016 at 06:17:01PM -0800, J Mo wrote:
> Package: libvirt-daemon
> Version: 2.4.0-1+b1
> Severity: important
> 
> I discovered today that setting "dynamic_ownership = 0" in
> /etc/libvirt/qemu.conf seems to break the creation of new VMs.
> 
> I set dynamic_ownership=0 because libvirt was improperly seizing 
> ownership of read-only ISO images.
> 
> Unfortunately, libvirt doesn't seem to be smart enough to change the
> permission of newly created .qcow2 files under /var/lib/libvirt/images
> when dynamic_ownership=0.
> 
> I get the following error with VMM/virt-manager when attempting to
> create a new VM:
> 
> 
> 
> Unable to complete install: 'internal error: qemu unexpectedly closed the monitor: 2016-11-11T02:00:33.137524Z qemu-system-x86_64: -drive file=/var/lib/libvirt/images/Debian_stable_test2.qcow2,format=qcow2,if=none,id=drive-virtio-disk0: Could not open '/var/lib/libvirt/images/Debian_stable_test2.qcow2': Permission denied'
> 
> Traceback (most recent call last):
>   File "/usr/share/virt-manager/virtManager/asyncjob.py", line 88, in cb_wrapper
>     callback(asyncjob, *args, **kwargs)
>   File "/usr/share/virt-manager/virtManager/create.py", line 2288, in _do_async_install
>     guest.start_install(meter=meter)
>   File "/usr/share/virt-manager/virtinst/guest.py", line 461, in start_install
>     doboot, transient)
>   File "/usr/share/virt-manager/virtinst/guest.py", line 396, in _create_guest
>     self.domain = self.conn.createXML(install_xml or final_xml, 0)
>   File "/usr/lib/python2.7/dist-packages/libvirt.py", line 3777, in createXML
>     if ret is None:raise libvirtError('virDomainCreateXML() failed', conn=self)
> libvirtError: internal error: qemu unexpectedly closed the monitor: 2016-11-11T02:00:33.137524Z qemu-system-x86_64: -drive file=/var/lib/libvirt/images/Debian_stable_test2.qcow2,format=qcow2,if=none,id=drive-virtio-disk0: Could not open '/var/lib/libvirt/images/Debian_stable_test2.qcow2': Permission denied

As far as I understand your report you're disabling the feature you
want: having libvirt fixup permissions. If you disable it you have (or
virt-manager) to do that.

There might be a bug in virt-manager where it should take more care of
adjusting permissions but it's hard to figure that out from your
report. You don't give virt-manager-versions, file permissions, etc or
what you did to get it to work.