Re: [PATCH v10 14/20] xen: introduce xenpv bus and a dummy pvcpu device

On 01/14/2014 04:08 PM, Roger Pau Monné wrote:
> On 14/01/14 16:41, Julien Grall wrote:
>> On 01/14/2014 02:59 PM, Roger Pau Monne wrote:
>>> +static int
>>> +xenpv_attach(device_t dev)
>>> +{
>>> +	device_t child;
>>> +
>>> +	if (xen_hvm_domain()) {
>>> +		device_t xenpci;
>>> +		devclass_t dc;
>>> +
>>> +		/* Make sure xenpci has been attached */
>>> +		dc = devclass_find("xenpci");
>>> +		if (dc == NULL)
>>> +			panic("unable to find xenpci devclass");
>>> +
>>> +		xenpci = devclass_get_device(dc, 0);
>>> +		if (xenpci == NULL)
>>> +			panic("unable to find xenpci device");
>>> +
>>> +		if (!device_is_attached(xenpci))
>>> +			panic("trying to attach xenpv before xenpci");
>>> +	}
>>
>> Can you use the identify method to add the xenpci device?
> 
> I don't think so, xenpci is a pci device, it is detected and plugged by
> the pci bus code.

Oups, I though you are trying to add the device. In this case, the check
seems pointless. In which case the xenpci couldn't exist?

-- 
Julien Grall