Re: [PATCH 2/4] target/hppa: defer hppa_ptlbe until CPU starts running

["Nicholas Piggin" <npiggin@gmail.com>]

On Wed Feb 26, 2025 at 5:38 AM AEST, Richard Henderson wrote:
> On 2/25/25 11:33, Richard Henderson wrote:
>> On 2/25/25 10:46, Alex Bennée wrote:
>>> @@ -191,7 +199,7 @@ static void hppa_cpu_realizefn(DeviceState *dev, Error **errp)
>>>           cpu->alarm_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL,
>>>                                           hppa_cpu_alarm_timer, cpu);
>>> -        hppa_ptlbe(&cpu->env);
>>> +        async_run_on_cpu(cs, hppa_clear_ptlbe, RUN_ON_CPU_HOST_PTR(&cpu->env));
>> 
>> Nack, this is emulation of hardware, not softmmu.
>
> Hmm.  I see what you're thinking about though: this function, after resetting the data 
> structures associated with the hardware emulation, also calls the softmmu flush.
>
> If we absolutely need to do so, I suppose delaying the hardware emulation flush to the 
> work queue isn't the worst solution.  This is where the hppa patch is more correct than 
> the ppc patch which completely eliminated the hardware emulation flush.

Could we expose a function that performs the hardware state reset,
and leave the TCG flushing to the TCG CPU reset?

Thanks,
Nick