Re: [Xen-devel] [RFC PATCH 1/8] x86/domctl: introduce a pair of hypercall to set and get cpu topology

[Chao Gao <chao.gao@xxxxxxxxx>]

On Tue, Jan 09, 2018 at 12:18:13PM -0500, Daniel De Graaf wrote:
>On 01/09/2018 04:06 AM, Chao Gao wrote:
>> On Mon, Jan 08, 2018 at 01:14:44PM -0500, Daniel De Graaf wrote:
>> > On 01/07/2018 11:01 PM, Chao Gao wrote:
>> > > Define interface, structures and hypercalls for toolstack to build
>> > > cpu topology and for guest that will retrieve it [1].
>> > > Two subop hypercalls introduced by this patch:
>> > > XEN_DOMCTL_set_cpu_topology to define cpu topology information per domain
>> > > and XENMEM_get_cpu_topology to retrieve cpu topology information.
>> > > 
>> > > [1]: during guest creation, those information helps hvmloader to build 
>> > > ACPI.
>> > > 
>> > > Signed-off-by: Chao Gao <chao.gao@xxxxxxxxx>
>> > 
>> > When adding new XSM controls for use by device models, you also
>> > need to add the permissions to the device_model macro defined in
>> > tools/flask/policy/modules/xen.if.  If domains need to call this
>> > function on themselves (is this only true for get?), you will also
>> > need to add it to declare_domain_common.
>> > 
>> 
>> Hi, Daniel.
>> 
>> Yes. XENMEM_get_cpu_topology will be called by the domain itself.
>> And Both get and set will be called by dom0 when creating one domain.
>> So I need:
>> 1. add *set* and *get* to create_domain_common.
>> 2. add *set* to declare_domain_common.
>> 
>> Is it right?
>> 
>> Thanks
>> Chao
>
>It sounds like you need to add get to declare_domain_common (not set)
>because the domain only needs to invoke this on itself.  If the device
>model doesn't need to use these hypercalls (would guest cpu hotplug or
>similar things need them?), then that's all you need to add.

Got it. I will first recognize whether device model needs these
hypercalls. If yes, make changes to macro device_model accordingly.

Thanks
chao

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel