Re: [PART1 V5 08/13] svm: Add interrupt injection via AVIC

[Suravee Suthikulpanit]

Hi,

Sorry for late response on this.

On 5/10/16 09:50, Paolo Bonzini wrote:
> On 10/05/2016 11:19, Borislav Petkov wrote:
> > > > This patch introduces a new mechanism to inject interrupt using AVIC.
> > > > Since VINTR is not supported when enable AVIC, we need to inject
> > 	"... is not supported when AVIC is enabled ..."
> >
> > VINTR?
>
> The ability to request a vmexit as soon as an interrupt can be injected
> (IF=GIF=1, no interrupt window, etc.).  It's called the "VINTR intercept".
>
> > Please write those things out in the commit message for maximum
> > information transfer to the reader. :)
>
> More important, where does the APM document that VINTR is not supported
> when AVIC is enabled?  It is certainly pointless and inefficient, but
> I'm not sure where it says that it doesn't work.
>
> Paolo

Basically, from the APM vol2 here:

  http://developer.amd.com/wordpress/media/2012/10/24593_APM_v21.pdf

On page 115, section AVIC EnableâVirtual Interrupt Control, Bit 31:

  "... Enabling AVIC implicitly disables the V_IRQ, V_INTR_PRIO,
   V_IGN_TPR, and V_INTR_VECTOR fields in the VMCB Control Word."

Thanks,
Suravee