Re: [v4] libxc: Expose the 1GB pages cpuid flag to guest

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 04/12/14 01:50, Zhang, Yang Z wrote:
> Konrad Rzeszutek Wilk wrote on 2014-12-03:
>> On Wed, Dec 03, 2014 at 09:38:49AM +0000, Ian Campbell wrote:
>>> On Tue, 2014-12-02 at 16:09 -0500, Konrad Rzeszutek Wilk wrote:
>>>> On Fri, Nov 28, 2014 at 11:50:43AM +0000, Ian Campbell wrote:
>>>>> On Fri, 2014-11-28 at 18:52 +0800, Liang Li wrote:
>>>>>> If hardware support the 1GB pages, expose the feature to guest by
>>>>>> default. Users don't have to use a 'cpuid= ' option in config fil
>>>>>> e to turn it on.
>>>>>>
>>>>>> If guest use shadow mode, the 1GB pages feature will be hidden from
>>>>>> guest, this is done in the function hvm_cpuid(). So the change is
>>>>>> okay for shadow mode case.
>>>>>>
>>>>>> Signed-off-by: Liang Li <liang.z.li@intel.com>
>>>>>> Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
>>>>> FTR although this is strictly speaking a toolstack patch I think the
>>>>> main ack required should be from the x86 hypervisor guys...
>>>> Jan acked it.
>>> For 4.5?
>> Probably not.
>>> Have you release acked it?
>> No.
>>> This seemed like 4.6 material to me, or at least I've not seen any
>>> mention/argument to the contrary.
>> Correct. 4.6 please.
> I think this more like a bug fixing than a feature. See our previous discussion.

It is allowing HVM guests to use a brand new hardware feature which was
previously unavailable to them.

It is absolutely not a bugfix, and not appropriate for 4.5 at this
point, but a good candidate for acceptance as soon as the 4.6 dev window
opens.

~Andrew