Re: [Qemu-devel] [RFC PATCH] ssi-sd: Make devices picking up backends unavailable with -device

[Philippe Mathieu-Daudé]

On 9/26/18 1:46 PM, Markus Armbruster wrote:
> Philippe Mathieu-Daudé <address@hidden> writes:
> 
>> Hi Markus,
>>
>> On 9/26/18 11:00 AM, Markus Armbruster wrote:
>>> Device models aren't supposed to go on fishing expeditions for
>>> backends.  They should expose suitable properties for the user to set.
>>> For onboard devices, board code sets them.
>>>
>>> Device ssi-sd picks up its block backend in its init() method with
>>> drive_get_next() instead.  This mistake is already marked FIXME since
>>> commit af9e40a.
>>>
>>> Unset user_creatable to remove the mistake from our external
>>> interface.  Since the SSI bus doesn't support hotplug, only -device
>>> can be affected.  Only certain ARM machines provide an SSI bus.
>>
>> There is also a MicroBlaze machine.
> 
> ssi-sd isn't linked into that one:
> qemu-system-microblaze: -device ssi-sd: 'ssi-sd' is not a valid device model 
> name
> 
>> Note that out of those target, we could model SSI buses on
>> southbridges/LPC devices but there is no interest.
>>
>> I'm also spending some hobby time on a MIPS SoC which exposes a SSI bus.
>>
>>> Signed-off-by: Markus Armbruster <address@hidden>
>>> ---
>>> Are there valid uses of -device ssi-sd?  If no, this patch is fine.
>>> If yes, this patch breaks them.  But fixing the FIXME will also break
>>> them.  What should we do?
>>
>> This device was probably orphan (not used) for a long time, and seems
>> unusable in it current state to me, see:
>> http://lists.nongnu.org/archive/html/qemu-devel/2018-06/msg01757.html
> 
> The more that's true, the less we have to worry about preserving
> compatibility ;)
> 
>> I have to address Peter's comment to my patch noted in my TODO (low
>> priority), so I'm OK to get ride of the FIXME.
>>
>> I suppose it is easier for you to get your patch in, then let me clean
>> that later.
> 
> Works for me.

So using 'user_creatable = false':
Acked-by: Philippe Mathieu-Daudé <address@hidden>