Re: [libvirt] [PATCH] conf: Fix parsing of seclabels without model

On Thu, Aug 30, 2012 at 13:19:31 -0300, Marcelo Cerri wrote: > With this patch libvirt tries to assign a model to seclabels when model > is missing. Libvirt will look up at host's capabilities and assign a > model in order to each seclabel that doesn't have a model assigned. > > This patch fixes: > > 1. The problem with existing guests that have a seclabel defined in its XML. > 2. A XML parse error when a guest is restored. > > Signed-off-by: Marcelo Cerri <mhcerri(a)linux.vnet.ibm.com&gt; > --- > src/conf/domain_conf.c | 56 ++++++++++++++++++++++++++------------------------ > 1 file changed, 29 insertions(+), 27 deletions(-) I think this is trying to fix the issue at a wrong place. It's not that XML generated by older libvirtd is not correctly parsed by current libvirtd. The problem is that *current* libvirtd creates an XML that it cannot parse back. Thus we should rather fix the code that formats the XML. On that front, I'm concerned about migration compatibility of this new security driver code. If we just blindly emit <seclabel type='dynamic' model='dac' relabel='yes'> element into the XML, I'm pretty sure an older libvirtd will complain about it even though the element was not used to do anything special that would be done anyway (that is, if labels are the default qemu_user:qemu_group).