Re: [PATCH v2 3/8] nvdimm acpi: introduce _FIT

[Xiao Guangrong <guangrong.xiao@linux.intel.com>]

On 10/10/2016 08:51 PM, Igor Mammedov wrote:
> On Sat, 8 Oct 2016 15:17:14 +0800
> Xiao Guangrong <guangrong.xiao@linux.intel.com> wrote:
>
>> On 09/30/2016 09:14 PM, Igor Mammedov wrote:
>>> On Fri, 12 Aug 2016 14:54:05 +0800
>>> Xiao Guangrong <guangrong.xiao@linux.intel.com> wrote:
>>>
>>>> _FIT is required for hotplug support, guest will inquire the updated
>>>> device info from it if a hotplug event is received
>>>>
>>>> As FIT buffer is not completely mapped into guest address space, so a
>>>> new function, Read FIT whose function index is 0xFFFFFFFF, is reserved
>>>> by QEMU to read the piece of FIT buffer. The buffer is concatenated
>>>> before _FIT return
>>> Only issuer of UUID 2F10E7A4-9E91-11E4-89D3-123B93F75CBA can reserve
>>> 0xFFFFFFFF for some purposes.
>>> So spec should be amended first or custom generated UUID should be used.
>>
>> Okay.
>>
>> I will change the changelog to reflect this fact and move the spec update
>> to this patch.
> under spec, I've meant ACPI spec where this UUID is declared

Er. ACPI spec just said that "0xFFFF is reserved", not sure it will be used
in the future.

I'd prefer to custom-generated UUID, however, currently the UUID is checked
in OSPM, i.e, QEMU is not able to distinguish other UUIDs, so how about
drop the UUID check in ACPI and pass the UUID info to QEMU?