Re: [Qemu-devel] [PATCH] hw/i386: Deprecate the machines pc-0.10 to pc-0.15

[Thomas Huth]

On 11.05.2017 09:06, Markus Armbruster wrote:
> Paolo Bonzini <address@hidden> writes:
> 
>> On 10/05/2017 16:47, Thomas Huth wrote:
>>>> So while we can delete pc-0.12, we can't delete associated features needed
>>>> by pc-0.12, without complicating RHEL's ability to create its back-compat
>>>> machine types. Downstream would have to un-delete the features.
>>>
>>> So I guess this is why Paolo said that pc-0.12 is still in "use" ... I
>>> think removing pc-0.12, but not removing rombar=0 will cause confusion
>>> in the upstream code base sooner or later,
>>
>> I agree.
>>
>>> so I guess we should rather
>>> keep the pc-0.12 machine until we can get rid of it together with the
>>> rombar code. We should still mark it as deprecated, of course.
>>>
>>>> I think tieing removal to major versions is a mistake, unless we're
>>>> going to set a fixed timeframe for delivery of major versions. ie if
>>>> we gaurantee that we'll ship a new major version every 18 months, that
>>>> gives people a predictable lifetime.  If we carry on inventing reasons
>>>> for major versions at arbitrary points in time, it makes it difficult
>>>> to have any reasonable forward planning.  It is more users friendly if
>>>> we can set a clear fixed timeframe for machine type lifecycle / eol
>>>
>>> IMHO we should have a new major release after we've reached a .9 minor
>>> release, but so far it seems like I'm the only one with that wish...
>>
>> I actually like that, but then you've pretty much guaranteed that you
>> _cannot_ remove anything deprecated until 4.0.  You and Daniel aren't
>> disagreeing as heavily as it seems, I think.
> 
> Even better: drop the '.', and stop worrying about having to wait for
> some arbitrary number to come up before you're allowed to do something
> ;)

I agree, we shouldn't limit ourselves by saying that we can only remove
things when switching to a new major release. But I still think that
also having "regular" major releases (e.g. after each .9 minor release)
could also help us to remind ourselves to do some bigger (and likely
necessary) spring-cleaning regularly.

 Thomas