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

[Markus Armbruster]

Thomas Huth <address@hidden> writes:

> On 2018-09-26 11:00, 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.
>> 
>> 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?
>> 
>>  hw/sd/ssi-sd.c | 2 ++
>>  1 file changed, 2 insertions(+)
>> 
>> diff --git a/hw/sd/ssi-sd.c b/hw/sd/ssi-sd.c
>> index 95a143bfba..ec7c7e6dbf 100644
>> --- a/hw/sd/ssi-sd.c
>> +++ b/hw/sd/ssi-sd.c
>> @@ -284,6 +284,8 @@ static void ssi_sd_class_init(ObjectClass *klass, void 
>> *data)
>>      k->cs_polarity = SSI_CS_LOW;
>>      dc->vmsd = &vmstate_ssi_sd;
>>      dc->reset = ssi_sd_reset;
>> +    /* Reason: init() method uses drive_get_next() */
>> +    dc->cannot_instantiate_with_device_add_yet = true;
>
> s/cannot_instantiate_with_device_add_yet = true/user_creatable = false/

Whoops, sent the pre-rebase patch instead of the post-rebase patch.

> Sounds like a good idea to me, if somebody then still needs this for
> "-device", they should fix the FIXME first.

Peter, what do you think?