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Subject: Re: [libvirt] [PATCH v2 1/2] vfio/mdev: add version attribute for
 mdev device
To:     Alex Williamson <alex.williamson@redhat.com>,
        Yan Zhao <yan.y.zhao@intel.com>,
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From:   Boris Fiuczynski <fiuczy@linux.ibm.com>
Date:   Wed, 8 May 2019 17:27:47 +0200
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On 5/8/19 11:22 PM, Alex Williamson wrote:
>>> I thought there was a request to make this more specific to migration
>>> by renaming it to something like migration_version.  Also, as an
>>>   
>> so this attribute may not only include a mdev device's parent device info and
>> mdev type, but also include numeric software version of vendor specific
>> migration code, right?
> It's a vendor defined string, it should be considered opaque to the
> user, the vendor can include whatever they feel is relevant.
> 
Would a vendor also be allowed to provide a string expressing required 
features as well as containing backend resource requirements which need 
to be compatible for a successful migration? Somehow a bit like a cpu 
model... maybe even as json or xml...
I am asking this with vfio-ap in mind. In that context checking 
compatibility of two vfio-ap mdev devices is not as simple as checking 
if version A is smaller or equal to version B.

-- 
Mit freundlichen Grüßen/Kind regards
    Boris Fiuczynski

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