Re: [Xen-devel] [PATCH v2] x86/apicv: fix RTC periodic timer and apicv issue

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 10.10.16 at 11:21, <xuquan8@xxxxxxxxxx> wrote:
> On September 26, 2016 2:39 PM, Jan Beulich < JBeulich@xxxxxxxx > wrote:
>>>>> On 24.09.16 at 03:06, <xuquan8@xxxxxxxxxx> wrote:
>>> On September 24, 2016 7:34 AM, Tian Kevin < kevin.tian@xxxxxxxxx > wrote:
>>>>> From: Jan Beulich [mailto:JBeulich@xxxxxxxx]
>>>>> Sent: Friday, September 23, 2016 11:34 PM
>>>>>
>>>>> >>> On 20.09.16 at 15:30, <xuquan8@xxxxxxxxxx> wrote:
>>>>> > --- a/xen/arch/x86/hvm/vlapic.c
>>>>> > +++ b/xen/arch/x86/hvm/vlapic.c
>>>>> > @@ -433,6 +433,12 @@ void vlapic_EOI_set(struct vlapic *vlapic)
>>>>> > void vlapic_handle_EOI(struct vlapic *vlapic, u8 vector)  {
>>>>> >      struct domain *d = vlapic_domain(vlapic);
>>>>> > +    struct vcpu *v = vlapic_vcpu(vlapic);
>>>>> > +    struct hvm_intack pt_intack;
>>>>> > +
>>>>> > +    pt_intack.vector = vector;
>>>>> > +    pt_intack.source = hvm_intsrc_lapic;
>>>>> > +    pt_intr_post(v, pt_intack);
>>>>>
>>>>> This also sits on the EOI LAPIC register write path, i.e. the change
>>>>> then also affects non-apicv environments.
>>>>
>>>>The new logic should be entered only when EOI-induced exit happens.
>>>>
>>>
>>> Yes, more that the EOI-induced exit is conditional, specifically, the
>>> bitmap is set by vmx_set_eoi_exit_bitmap().
>>> Jan, what do you think? While I recall from v1 discussion, you have
>>> the same comment. We can dig it deep..
>>
>>See my reply to Kevin sent a minute ago. As I'm not sure what Kevin means to
>>state with several of his responses, I can't properly respond for now. And 
>>then
>>what you say doesn't really address my concern - things being conditional
>>elsewhere doesn't mean we won't get here too in the non-apicv case, at least
>>not in a way that I can follow right away.
> 
> Jan, any idea now? 

I don't think there was anything left open on the other sub-thread;
if there is, please point out specific aspects which are still unclear.

Jan


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