Re: [Xen-devel] [PATCH] libxc: Expose the pdpe1gb cpuid flag to guest

["Zhang, Yang Z" <yang.z.zhang@xxxxxxxxx>]

Tim Deegan wrote on 2014-11-19:
> At 01:29 +0000 on 19 Nov (1416356943), Zhang, Yang Z wrote:
>> Tim Deegan wrote on 2014-11-18:
>>> In this case, the guest is entitled to _expect_ pagefaults on 1GB
>>> mappings if CPUID claims they are not supported.  That sounds like
>>> an unlikely thing for the guest to be relying on, but Xen itself
>>> does something similar for the SHOPT_FAST_FAULT_PATH (and now also
>>> for IOMMU entries for the deferred caching attribute updates).
>> 
>> Indeed. How about adding the software check (as Andrew mentioned)
>> firstly and leave the hardware problem (Actually, I don't think we
>> can solve it currently).
> 
> I don't think we should change the software path unless we can change
> the hardware behaviour too.  It's better to be consistent, and it
> saves us some cycles in the pt walker.

So if we don't need to add the software check, does this mean current patch is 
ok?

> 
> Cheers,
> 
> Tim.


Best regards,
Yang



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