Bug 1699051

When support was added for firewalld using an nftables backend, part of the implementation required adding a new firewalld zonefile called "libvirt" that uses a new firewalld feature - the ability to set a priority for each rich rule in a zone.

Anticipating that some distros would get an updated libvirt package before they got an updated firewalld package, the support for the libvirt zonefile was made contingent on a --with-firewalld-zone configure option. In the libvirt.spec file, we set this flag on if the Fedora version was 30+ (since the F30 release was at that time several months in the future), but the GA of F30 is now imminent, and the F30 firewalld package hasn't yet been updated to support rich rule priorities (most likely because there hasn't been a new upstream release of firewalld since that feature was added.

The presence of the libvirt zonefile in a system that has a firewalld that doesn't support rich rule priorities will result in this error message every time firewalld is started/restarted:

firewalld[13355]: ERROR: Failed to load zone file '/usr/lib/firewalld/zones/libvirt.xml': PARSE_ERROR: rule: Unexpected attribute priority


Since the F30 firewalld has a patch to make iptables the default backend, the libvirt zone isn't needed for proper networking, so there is no *functional* problem, but users may be confused by the above error message and unnecessarily file bug reports. So we could decide to continue installing the libvirt zonefile (in anticipation of the F30 firewalld being updated to support rich rule priorities), or we could decide to patch the libvirt.spec to only install the libvirt zonefile for F31+, and avoid the error logs (if we do this, we should probably do it upstream and backport the patch rather than just making it a downstream patch).