Re: [Xen-devel] [Patch RFC 00/13] VT-d Asynchronous Device-TLB Flush for ATS Device

["Xu, Quan" <quan.xu@xxxxxxxxx>]

>>> On 21.09.15 at 20:04, < JBeulich@xxxxxxxx > wrote:
> >>> On 21.09.15 at 11:46, <quan.xu@xxxxxxxxx> wrote:
> >>> >>> On 21.09.15 at 16:51, < JBeulich@xxxxxxxx > wrote:
> >>- Anything else?
> >
> >
> > Just test the extreme case. The ATS specification mandates a timeout
> > of 1 _minute_ for cache flush, even though it doesn't take so much
> > time for cache flush.
> > In my design, if the Device-TLB is not completed, the domain's vCPUs
> > are not allowed entry guest mode (patch #7), otherwise, the logic is not
> correct.
> 
> Hmm, that would be a serious limitation, and I can't immediately see a reason:
> Taking this with virtualization removed, I don't think such an invalidation 
> would
> stall a physical CPU for a whole minute. Sadly I also can't immediately think 
> of a
> solution, but I guess first of all I'll have to take a look at the series 
> (which
> unfortunately may take a few days to get to).
> 
> Jan

Jan, 

thanks for your review. Any comment, I will reply to your emails ASAP.
 
-Quan 

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