Re: [PATCH 0/4] hw/s390x: Alias @dump-skeys -> @dump-s390-skey and deprecate

[Thomas Huth <thuth@redhat.com>]

On 09/03/2025 19.55, Pierrick Bouvier wrote:
> On 6/3/24 05:18, Daniel P. Berrangé wrote:
>> On Fri, May 31, 2024 at 06:47:45AM +0200, Thomas Huth wrote:
>>> On 30/05/2024 09.45, Philippe Mathieu-Daudé wrote:
>>>> We are trying to unify all qemu-system-FOO to a single binary.
>>>> In order to do that we need to remove QAPI target specific code.
>>>>
>>>> @dump-skeys is only available on qemu-system-s390x. This series
>>>> rename it as @dump-s390-skey, making it available on other
>>>> binaries. We take care of backward compatibility via deprecation.
>>>>
>>>> Philippe Mathieu-Daudé (4):
>>>>     hw/s390x: Introduce the @dump-s390-skeys QMP command
>>>>     hw/s390x: Introduce the 'dump_s390_skeys' HMP command
>>>>     hw/s390x: Deprecate the HMP 'dump_skeys' command
>>>>     hw/s390x: Deprecate the QMP @dump-skeys command
>>>
>>> Why do we have to rename the command? Just for the sake of it? I think
>>> renaming HMP commands is maybe ok, but breaking the API in QMP is something
>>> you should consider twice.
>>
>> That was going to be my question too. Seems like its possible to simply
>> stub out the existing command for other targets.
>>
>> The renaming is just window dressing.
>>
> 
> Working on single-binary topic means specificities from every qemu binary/ 
> architecture has to be merged together. Despite appearing has a bad thing 
> now, it's definitely a step forward for QEMU, and will allow to enable new 
> usages.
> 
> The hard way is to trigger a deep refactoring, involving lengthy 
> conversations where compromises have to be found ("let's implement this for 
> all arch"). The pragmatic way is to eliminate obvious stuff.
> 
> This command is specific to an arch, so renaming is a good and obvious 
> strategy. For the backward compatible anxious developer, another strategy 
> would be to simply declare this command if the running target is s390x. But 
> then, you create a precedent to do something that should not have existed in 
> the first place. 
> 
> +1 for the renaming, and hope that users of this command are able to change 
> a line in their script to adapt to the new command.

Sorry, but no: We've got plenty of other target specific commands... 
rtc-reset-reinjection , query-sev, query-gic-capabilities, just to name some 
few. So unless you provide a patch series to rename *all* of them and 
deprecate the previous names, I don't see the point why changing just one 
single s390x command is necessary.

  Thomas