Re: [Xen-devel] [PATCH 3/7] Nested VMX: Force check ISR when L2 is running

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 11.08.13 at 04:49, "Zhang, Yang Z" <yang.z.zhang@xxxxxxxxx> wrote:
> Jan Beulich wrote on 2013-08-09:
>>>>> On 09.08.13 at 10:49, Yang Zhang <yang.z.zhang@xxxxxxxxx> wrote:
>>> From: Yang Zhang <yang.z.zhang@xxxxxxxxx>
>>> 
>>> If L2 is running, external interrupt is allowed to notify CPU only
>>> when it has higher priority than current in servicing interrupt.
>> 
>> That's always this way, not just for nested HVM. Hence there must
>> either be some piece missing from this explanation, or the check is
>> being inserted in the wrong place.
> How about change the comments like this:
> External interrupt is allowed to notify CPU only when it has higher priority 
> than current in servicing interrupt. With APIC-v, the priority comparing is 
> done by hardware and hardware will inject the interrupt to VCPU when it 
> recognizes an interrupt. Currently, there is no virtual APIC-v feature 
> available for L1, so when L2 is running, we still need to compare interrupt 
> priority with ISR in hypervisor instead hardware.

Yes, that would make things quite a bit more clear.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel