From mboxrd@z Thu Jan  1 00:00:00 1970
From: Markus Armbruster <armbru@redhat.com>
Subject: Re: [Qemu-devel] Re: [PATCH v3] qemu, qmp: convert do_inject_nmi() to QObject, QError
Date: Thu, 16 Dec 2010 10:42:35 +0100
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Cc: qemu-devel@nongnu.org, aliguori@us.ibm.com,
	Avi Kivity <avi@redhat.com>, kvm@vger.kernel.org,
	Lai Jiangshan <laijs@cn.fujitsu.com>
To: Luiz Capitulino <lcapitulino@redhat.com>
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In-Reply-To: <20101215160000.16f85795@doriath> (Luiz Capitulino's message of
	"Wed, 15 Dec 2010 16:00:00 -0200")
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Luiz Capitulino <lcapitulino@redhat.com> writes:

> On Wed, 15 Dec 2010 18:45:09 +0100
> Markus Armbruster <armbru@redhat.com> wrote:
>
>> Luiz Capitulino <lcapitulino@redhat.com> writes:
>> 
>> > On Wed, 15 Dec 2010 19:18:32 +0200
>> > Avi Kivity <avi@redhat.com> wrote:
[...]
>> >> I'd like to see cpu-index made optional; if not present, nmi all cpus 
>> >> (that's what the nmi button on many machines does, or at least I think 
>> >> that's what it does).
>> >
>> > Looks like a GUI feature to me,
>> 
>> Really?  Can't see how you can build "NMI to all CPUs" from "NMI this
>> CPU".  Or am I misunderstanding you?
>
> I guess so. Avi referred to 'nmi button on many machines', I assumed he
> meant a virtual machine GUI, am I wrong?
>
>> >                                 _might_ turn out to be an undesirable
>> > side effect to client writers.
>> 
>> They seem to be coping fine with optional arguments elsewhere.
>
> Which we might want to review.
>
>> >                                I guess I prefer a to-all-cpus argument.
>> 
>> How would that look like?  "cpu-index": "all"?
>
> Like this:
>
> { "execute": "inject-nmi", "arguments": { "to-all-cpus": true } }
>
> But this looks like an optimization to me, because it's also easy to do:
>
> for cpu in query-cpus; do
>   inject-nmi cpu
>
> Unless we want to do this in an "atomic" way, due to side effects I'm
> not aware about.

I'd expect a physical NMI button to interrupt all CPUs simultaneously
(modulo wire length).

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