Re: [PATCH v2] hw/sparc64/sun4u: Mark unusable PCI busses as full to ease device plugging

On 09/06/2026 08.02, Thomas Huth wrote:
> On 08/06/2026 23.29, Mark Cave-Ayland wrote:
>> On 08/06/2026 09:26, Michael Tokarev wrote:
>>
>>> On 30.04.2026 12:50, Thomas Huth wrote:
>>>> On 09/03/2026 19.14, Thomas Huth wrote:
>>>>> From: Thomas Huth <[email protected]>
>>>>>
>>>>> When trying to plug a PCI device to a Sparc64 machine, you currently
>>>>> have to specify the right bus ("bus=pciB"), otherwise you get this error:
>>>>>
>>>>>   $ qemu-system-sparc64 -device virtio-scsi-pci
>>>>>   qemu-system-sparc64: -device virtio-scsi-pci: PCI: no slot/function
>>>>>   available for virtio-scsi-pci, all in use or reserved
>>>>>
>>>>> This is quite annoying for the unexperienced users, and it also breaks
>>>>> e.g. the iotests ("make check-block") when running with qemu-system- 
>>>>> sparc64.
>>>>>
>>>>> Mark the non-usable PCI busses as full now, so that QEMU can automatically
>>>>> plug new PCI devices to the right "pciB" bus.
>>>>>
>>>>> Signed-off-by: Thomas Huth <[email protected]>
>>>>> ---
>>>>>   v2: Do the change in the machine code, not in the sabre device
>>>>>
>>>>>   hw/sparc64/sun4u.c | 7 +++++++
>>>>>   1 file changed, 7 insertions(+)
>>>>>
>>>>> diff --git a/hw/sparc64/sun4u.c b/hw/sparc64/sun4u.c
>>>>> index b8bda1eb816..37539535c6c 100644
>>>>> --- a/hw/sparc64/sun4u.c
>>>>> +++ b/hw/sparc64/sun4u.c
>>>>> @@ -723,6 +723,13 @@ static void sun4uv_init(MemoryRegion 
>>>>> *address_space_mem,
>>>>>       fw_cfg_add_i16(fw_cfg, FW_CFG_SPARC64_DEPTH, graphic_depth);
>>>>>       qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
>>>>> +
>>>>> +    /*
>>>>> +     * Mark internal PCI busses as full so that the plugging of 
>>>>> additional
>>>>> +     * PCI devices happens on the right bus that still has free slots:
>>>>> +     */
>>>>> +    qbus_mark_full(&pci_bus->qbus);
>>>>> +    qbus_mark_full(&pci_busA->qbus);
>>>>>   }
>>>>>   enum {
>>>>
>>>> Friendly ping!
>>>
>>> This, being a simple change, somehow has not been reviewed still, so
>>> it's sitting in the queue...
>>
>> Yes, apologies - I've been absolutely flat out recently, and I've got a 
>> note to take a look at this and Peter's patch as soon as I can.
>>
>> Is this fixing an urgent issue with "make check-block" or similar?
> 
> It's not urgent since this has been broken forever, but yes, it fixes "make 
> check-block" for the case where sparc64 is the only available target during 
> "configure --target-list=sparc64-softmmu" and thus the iotests run with 
> qemu-system-sparc64.
Ping!

While it's not urgent, soft-freeze date is in a week, so it would be nice to 
get this merged before it misses another release ... WDYT?

  Thanks,
   Thomas