Re: [PATCH] target/loongarch: Add full type support for query-cpu-model-expansion

[David Hildenbrand <david@redhat.com>]

On 13.02.25 17:17, Igor Mammedov wrote:
> On Thu, 13 Feb 2025 12:48:30 +0100
> Markus Armbruster <armbru@redhat.com> wrote:
> 
>> gaosong <gaosong@loongson.cn> writes:
>>
>>> Cc: Markus
>>>
>>> hi, Markus
>>>
>>> What is the difference between CPU_MODEL_EXPANSION_TYPE_STATIC and
>>> CPU_MODEL_EXPANSION_TYPE_FULL?
> 
> the only difference is that 'static' expansion will not report properties
> not mentioned in hard-codded CPU model definition see: builtin_x86_defs
> 
> while 'full' will iterate over/report all rw properties of CPU object
> created from provided model name.
> 
>> I don't know :)
>>
>> Here's the documentation:
>>
>>      ##
>>      # @CpuModelExpansionType:
>>      #
>>      # An enumeration of CPU model expansion types.
>>      #
>>      # @static: Expand to a static CPU model, a combination of a static
>>      #     base model name and property delta changes.  As the static base
>>      #     model will never change, the expanded CPU model will be the
>>      #     same, independent of QEMU version, machine type, machine
>>      #     options, and accelerator options.  Therefore, the resulting
>>      #     model can be used by tooling without having to specify a
>>      #     compatibility machine - e.g. when displaying the "host" model.
>>      #     The @static CPU models are migration-safe.
> 
> Looking at related x86 code above description sounds like a fiction.

On s390x, which added that interface, that is how it's work.

It resolves to "-base" models that are fixed for all eternity.

x86-64 probably didn't adhere to the description because they were not 
interested in adding stable base models.

-- 
Cheers,

David / dhildenb