Re: [Xen-devel] [PATCH] x86: add feature flags to shared_info page

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 02.03.15 at 14:44, <andrew.cooper3@xxxxxxxxxx> wrote:
> On 02/03/15 13:15, Jan Beulich wrote:
>>>>> On 02.03.15 at 13:59, <"jgross@xxxxxxxx".non-mime.internet> wrote:
>>> In order to indicate the Xen tools capability to support the virtual
>>> mapped linear p2m list instead the 3 level mfn tree add feature flags
>>> to the shared_info page.
>> But why in the shared info page? They'd belong to start info or should
>> be obtainable via XENVER_get_features.
> 
> Furthermore in this case, the virtual linear p2m is purely a
> guest->toolstack feature/ABI.
> 
> Xen deliberately has no knowledge of PV guest p2ms of either the 3level
> or linear variety.
> 
> Is there genuinely no better interface than the hypervisor feature flags
> to indicate a piece of toolstack support?

As Ian indicated in his reply, much depends on whether any other
mechanism would allow the information to be retrieved early enough
in the guest.

Jan


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