[PATCH v6] KVM: arm/arm64: Route vtimer events to user space

[Paolo Bonzini]

On 23/09/2016 14:36, Alexander Graf wrote:
>>>
>>> +        if ((ret == 1) && timer_ret) {
>>> +            /*
>>> +             * We have to exit straight away to ensure that we only
>>> +             * ever notify user space once about a level change
>>> +             */
>>
>> Is this really a requirement?  It complicates the logic noticeably.
> 
> The alternative would be to track the state on ioctl entry, which
> Christoffer disliked :).

Ok, I see.  Maybe he's convinced by the ugly code. :)

It's not an architectural concept, it's a KVM API concept.  Tracking the
state on entry just the equivalent of making this vmexit edge-triggered
(both rising and falling edge).

Paolo