[Qemu-devel] Re: [PATCH] Revive -version 'QEMU PC Emulator...'

[Cole Robinson <crobinso@redhat.com>]

On 05/13/2010 04:35 AM, Jes Sorensen wrote:
> On 05/12/10 22:48, Cole Robinson wrote:
>> I agree libvirt's method is a crappy approach. Adding a proper -version
>> argument is certainly the way forward, but doesn't help users with
>> existing libvirt installations that want to use latest qemu. This is the
>> type of issue that libvirt devs will be fielding for months. Ideally i'd
>> like the order to be:
>>
>> 1) Apply this patch
>> 2) Add a proper -version argument, maybe named -version_num
>> 3) libvirt patched to use new version argument (and robustify legacy
>> version parsing)
>> 4) Some reasonable amount of time from now (6 months, a year?), edit the
>> current -version string at will
>>
>> I'd be willing to do 2 and 3 if people agree.
> 
> Hi Cole,
> 
> I think rather than 1, it would be better to add a patch to libvirt to
> catch both formats. I know Chris Lalancette already cooked up a patch
> for this. Combined with the 2) patch I just posted, and 3) I think that
> should take care of the problems.
> 

It doesn't solve the problem for existing libvirt installations. It's
not uncommon for users to track just the latest kvm releases without
upgrading libvirt: any future qemu or kvm release will break every
version of libvirt that exists today. Given that unfortunate case, I
still recommend reverting the 'PC' change at least for long enough for a
few fixed libvirt releases to make it into the wild.

- Cole