On 09/04/2012 12:15 PM, Paolo Bonzini wrote: > Il 04/09/2012 10:16, Avi Kivity ha scritto: >>> > But the point of subsections is to succeed migration in the common case, >>> > assuming there is more than one case that doesn't affect guest operation. >> According to the patch, if icw3 == 4 && !(eclr & 4), then behaviour will >> change. With the standard configuration, if two pci interrupts hit at >> once, then before the patch irr.2 will be clear, and afterwards set. >> >> So we do have a behavioural change. Is the rest of the code masking >> this change under the standard configuration? > > No, it is not masking the change. The assumption is that nothing should > care about irr.2 or isr.2, because nothing attaches an handler to the > cascade interrupt.
Won't the next call to pic_get_irq() notice the difference in s->irr? > You have to choose between assuming this, and breaking backwards > migration. I would rather break backwards migration, but others disagree... Normally I'd agree, but if the only known breakee is a 1987 guest then I'd make an exception. -- error compiling committee.c: too many arguments to function
