From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Subject: Re: [PATCH v2 08/18] nvdimm: init backend memory mapping and config
 data area
Date: Mon, 31 Aug 2015 14:23:43 +0800
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Cc: Stefan Hajnoczi <stefanha@gmail.com>, pbonzini@redhat.com,
	imammedo@redhat.com, gleb@kernel.org, mtosatti@redhat.com,
	mst@redhat.com, rth@twiddle.net, ehabkost@redhat.com,
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To: Stefan Hajnoczi <stefanha@redhat.com>
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Hi Stefan,

On 08/28/2015 07:58 PM, Stefan Hajnoczi wrote:

>
>>>> +        goto do_unmap;
>>>> +    }
>>>> +
>>>> +    nvdimm->device_index = new_device_index();
>>>> +    sprintf(name, "NVDIMM-%d", nvdimm->device_index);
>>>> +    memory_region_init_ram_ptr(&nvdimm->mr, OBJECT(dev), name, nvdimm_size,
>>>> +                               buf);
>>>
>>> How is the autogenerated name used?
>>>
>>> Why not just use "pc-nvdimm.memory"?
>>
>> Ah. Just for debug proposal :) and i am not sure if a name used for multiple
>> MRs (MemoryRegion) is a good idea.
>
> Other devices use a constant name too (git grep
> memory_region_init_ram_ptr) so it seems to be okay.  The unique thing is
> the OBJECT(dev) which differs for each NVDIMM instance.
>

When I was digging into live migration code, i noticed that the same MR name may
cause the name "idstr", please refer to qemu_ram_set_idstr().

Since nvdimm devices do not have parent-bus, it will trigger the abort() in that
function.