Re: [Qemu-devel] [PATCH 2/2 V7] qemu,qmp: add inject-nmi qmp command

[Jan Kiszka]

On 2011-04-06 20:08, Luiz Capitulino wrote:
> On Wed, 06 Apr 2011 13:03:37 -0500
> Anthony Liguori <address@hidden> wrote:
> 
>> On 04/06/2011 12:47 PM, Luiz Capitulino wrote:
>>> On Mon, 04 Apr 2011 08:05:48 -0500
>>> Anthony Liguori<address@hidden>  wrote:
>>>
>>>> On 04/04/2011 07:54 AM, Avi Kivity wrote:
>>>>> On 04/04/2011 01:59 PM, Daniel P. Berrange wrote:
>>>>>> Interesting that with HMP you need to specify a single CPU index, but
>>>>>> with QMP it is injecting to all CPUs at once. Is there any compelling
>>>>>> reason why we'd ever need the ability to only inject to a single CPU
>>>>>> from an app developer POV ?
>>>>> When a PC has an NMI button, it is (I presume) connected to all CPUs'
>>>>> LINT1 pin, which is often configured as an NMI input.  So the all-cpu
>>>>> variant corresponds to real hardware, while the single-cpu variant
>>>>> doesn't.
>>>>>
>>>>> wrt the app developer POV, the only use I'm aware of is that you can
>>>>> configure Windows to dump core when the NMI button is pressed and thus
>>>>> debug driver problems.  It's likely more reliable when sent to all cpus.
>>>> It either needs to be removed from HMP or added to QMP.  HMP shouldn't
>>>> have more features than QMP (even if those features are non-sensible).
>>> Is anyone against changing HMP behavior to send it to all CPUs?
>>
>> Makes sense to me.
> 
> So, Lai, in order to get this merged could you please do the following:
> 
>  1. Address checkpath.pl errors
> 
>  2. Change the HMP to use this implementation, which send the NMI
>     to all CPUs

HMP is currently x86-only, thus it's probably OK to model it after some
PC feature (though I don't know if there aren't NMI buttons with BP-only
wirings). But will the consolidate version be defined for all
architectures? We should avoid "exporting" x86-specific assumptions.

Jan

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