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

[Anthony Liguori]

On 04/08/2011 02:17 PM, Blue Swirl wrote:
> On Fri, Apr 8, 2011 at 9:04 AM, Gleb Natapov<address@hidden>  wrote:
> > On Thu, Apr 07, 2011 at 04:41:03PM -0500, Anthony Liguori wrote:
> > > On 04/07/2011 02:17 PM, Gleb Natapov wrote:
> > > > On Thu, Apr 07, 2011 at 10:04:00PM +0300, Blue Swirl wrote:
> > > > > On Thu, Apr 7, 2011 at 9:51 PM, Gleb Natapov<address@hidden>    wrote:
> > > > >
> > > > > I'd prefer something more generic like these:
> > > > > raise /address@hidden:l1int
> > > > > lower /i44FX-pcihost/address@hidden/pinD
> > > > >
> > > > > The clumsier syntax shouldn't be a problem, since this would be a
> > > > > system developer tool.
> > > > >
> > > > > Some kind of IRQ registration would be needed for this to work without
> > > > > lots of changes.
> > > > True. The ability to trigger any interrupt line is very useful for
> > > > debugging. I often re-implement it during debug.
> > > And it's a good thing to have, but exposing this as the only API to
> > > do something as simple as generating a guest crash dump is not the
> > > friendliest thing in the world to do to users.
> > Well, this is not intended to be used by regular users directly and
> > management can provide nicer interface for issuing NMI. But really,
> > my point is that NMI actually generates guest core dump in such rare
> > cases (only preconfigured Windows guests) that it doesn't warrant to
> > name command as such. Management is in much better position to implement
> > functionality with such name since it knows what type of guest it runs
> > and can tell agent to configure guest accordingly.
> Does the management need to know about each and every debugging
> oriented interface? For example, "info regs",  "info mem", "info irq"
> and tracepoints?
>
> I think giving IRQs symbolic names could solve some other problems as
> well. Maybe it should be possible to connect IRQs in a configuration
> file and even with command line:
> -device port90,irqid=p90out -device pckbd,irqid=kbdout -device
> and,in=p90out,in=kbdout,out=sreset device system_reset,in=sreset

You really want devices to have properties and for the device properties 
to be discoverable.  For instance:

struct DeviceInfo
{
     .name = "and",
     .properties = {
          DEFINE_IRQ_IN(AndDevice, in[0]),
          DEFINE_IRQ_IN(AndDevice, in[1]),
          DEFINE_IRQ_OUT(AndDevice, out),
     },
};

And then you can do:

-device port90,id=port90 -device pckbd,id=pckbd \
-device and,in[0]=port90.out,in[1]=pckbd.out,id=reset_and \
-device system_reset.in=reset_and

Regards,

Anthony Liguori

> or
>
>   -device 
> and,in=/i44FX-pcihost/PIIX3/i8042/out1,in=/i44FX-pcihost/PIIX3/p90/out1,out=/QEMU/system_reset