Re: nmi is broken?

[OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>]

Avi Kivity <avi@redhat.com> writes:

> On 05/03/2011 12:36 PM, Avi Kivity wrote:
>>
>>> I don't know about live migration of kvm. If we said the wiring is like
>>> figure 5-2, what is required for the live migration? It was required
>>> only if IMCR was required?
>>
>> The issue with live migration is that we can't change the running 
>> configuration while the system is running, like adding the IMCR or 
>> changing the wiring.  The hardware will be programmed for the old 
>> configuration and will likely fail with the new one.  For example, the 
>> current wiring has the PIT output wired to PIC IRQ0 and IOAPIC INTI0; 
>> we need to change it to IOAPIC INTI2 instead.
>>
>
> btw, I believe that the configuration currently implemented is legal 
> (it's similar to config 7 in table 5-2 of the mpspec); the only problem 
> is that it can't support the NMI watchdog through the I/O APIC trick, 
> yet we allow it through a hack.

I'm confused a bit. "config 7 in table 5-2" says PIT output wired to
IOAPIC INTIN2. So, we don't need to change it?

> Something we can do is connect the 8259A output to the I/O APIC INTIN2; 
> it should be masked so live migration will continue to work.  We just 
> have to make sure that the guest is able to find that it is connected there.

8259A INTR to IOAPIC INTIN2 sounds strange. Isn't it IOAPIC INTIN0?

Thanks.
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>