Re: LAPIC soft-disable vs. LVT masking

["Yang, Sheng" <sheng.yang@intel.com>]

On Monday 20 October 2008 16:49:11 Jan Kiszka wrote:
> Hi Sheng,
>
> obviously, I meditated too long over the APIC specs and VAPIC code of
> KVM: When the guest resets the soft-enable bit in SVR, the in-kernel
> APIC implementation also set the LVT masked bits - so far, so fine
> (according to specs). But I failed to read out of that doc if those mask
> bits are permanently set (until the guest clears them again) or only
> until the soft-disabling ends (ie. they are restored to their previous
> state - QEMU goes this way). Can you clarify?
>
> Thanks,
> Jan
>
Hi Jan

I also can't find related info in the spec. But I think, when software enable 
bit is cleaned, the spec said the mask bits are set, which means the content 
of register is changed. And no words for what happen if set software enable 
bit, so I think it maybe retain the mask state after software enable (a 
little more possibility).

I will give a update if I got more infos.
--
regards
Yang, Sheng