Re: [Qemu-ppc] [PATCH v2 2/6] add QemuSupportState

[Paolo Bonzini]

On 06/11/2018 15:26, Eduardo Habkost wrote:
> On Tue, Nov 06, 2018 at 11:23:31AM +0100, Gerd Hoffmann wrote:
>> Indicates support state for something (device, backend, subsystem, ...)
>> in qemu.  Add QemuSupportState field to ObjectClass.  Add some support
>> code.
>>
>> TODO: wire up to qom-list-types
>>
>> Signed-off-by: Gerd Hoffmann <address@hidden>
>> ---
> [...]
>> +##
>> +# @SupportState:
>> +#
>> +# Indicate Support level of qemu devices, backends, subsystems, ...
>> +#
>> +# @unspecified: not specified (zero-initialized).
>> +#
>> +# @experimental: in development, can be unstable or incomplete.
> 
> People reading this document would ask: what would appear on
> MAINTAINERS if SupportState is `experimental`?

Probably Maintained.  It's something that is on its way towards becoming
"supported", but still too immature ("unstable or incomplete").

>> +#
>> +# @supported: works stable and is fully supported.
>> +#             (supported + maintained in MAINTAINERS).
>> +#
>> +# @unsupported: should work, support is weak or not present.
>> +#               (odd-fixes + orphan in MAINTAINERS).
> 
> What's the difference in practice between unsupported and
> experimental?
> 
>> +#
>> +# @obsolete: is obsolete, still present for compatibility reasons,
>> +#            will likely be removed at some point in the future.

I am not sure this is necessarily true.  I don't see Cirrus or adlib or
pcnet disappearing anytime soon.

Paolo

>> +#            Not deprecated (yet).
>> +#            (obsolete in MAINTAINERS).
>> +#
>> +# @deprecated: is deprecated, according to qemu deprecation policy.
> 
> I believe we want to differentiate "deprecated, but still safe to
> use in production if you have a migration plan" from "deprecated,
> and also unstable and unsafe for production".
> 
> I expect enterprise distributions to have a strict policy of not
> allowing unsupported and experimental devices to be enabled, but
> still allow deprecated devices to be enabled (but only if they
> are stable/supported).
>