Am 10.08.2011 um 06:42 schrieb Paul Mackerras <paulus@xxxxxxxxx>: > On Tue, Aug 09, 2011 at 06:31:48PM +0200, Alexander Graf wrote: > >> Now that Book3S PV mode can also run PAPR guests, we can add a PAPR cap and >> enable it for all Book3S targets. Enabling that CAP switches KVM into PAPR >> mode. > > Don't we want to enable it only for 64-bit hosts? Trying to run a > PAPR guest on a 32-bit Book 3S host won't work very well, unless I am > missing something... I agree that it doesn't make sense, but if anything we should restrict it to 64-bit _guests_. you can also run 32-bit guests on 64-bit hosts. And so far, we don't have a single interface setting PVR and PAPR mode at the same time, so you could still enable PAPR with a 64-bit guest CPU and then switch to a 32-bit CPU. It'd be a nightmare to check all configurations on every setter function. Unless... We could introduce a sanity check function that gets executed every time we change PVR or enable PAPR. That could set a variable in the vcpu struct to indicate that the config is ok. We could then check that on vcpu_run. Alex > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
