Re: [libvirt] [Qemu-devel] [PULL 25/26] block: Remove deprecated -drive option serial

On Tue, Jul 10, 2018 at 17:01:22 +0200, Cornelia Huck wrote: > On Tue, 10 Jul 2018 16:39:31 +0200 > Peter Krempa <pkrempa(a)redhat.com&gt; wrote: >> On Tue, Jul 10, 2018 at 16:22:08 +0200, Cornelia Huck wrote: >>> On Tue, 10 Jul 2018 07:59:15 +0200 >>> Markus Armbruster <armbru(a)redhat.com&gt; wrote: [...] >>> "ERROR: 'old_option' is deprecated and will be removed; use 'modern_option' instead" >>> >>> and do an exit(1). >>> >>> Would that be workable? >> >> For delivering the warnings via monitor you'll need a store that will >> collect all the warnings and prepare them for delivery. You've got >> basically two options: >> >> 1) monitor command to poll for deprecated options >> 2) event with deprecated options >> >> Both require storing them since libvirt connects to the monitor only >> after the command line is processed. >> >> Warnings printed to stderr are nearly useless because until something >> breaks nobody bothers to read the log files. > > So, from that I gather that a hard failure would be the easiest for > libvirt to detect (and everything else would become complicated really > quickly), right? People start complaining only when stuff breaks. If anything is optional people will usually not enable it. That makes any non-mandatory option not work in most cases.