Re: [Qemu-devel] [v5][PATCH 4/5] xen, gfx passthrough: create host bridge to passthrough

["Chen, Tiejun" <tiejun.chen@intel.com>]

On 2014/6/25 14:24, Paolo Bonzini wrote:
> Il 25/06/2014 04:17, Tiejun Chen ha scritto:
>> +    if (xen_enabled() && xen_has_gfx_passthru) {
>> +        d = pci_create_simple(b, 0, TYPE_I440FX_XEN_PCI_DEVICE);
>> +        *pi440fx_state = I440FX_XEN_PCI_DEVICE(d);
>> +        pci_create_pch(b);
>> +    } else {
>> +        d = pci_create_simple(b, 0, TYPE_I440FX_PCI_DEVICE);
>> +        *pi440fx_state = I440FX_PCI_DEVICE(d);
>> +    }
>
> As mentioned in the review of v4, this should be a separate,
> Xen-specific machine.  pci_create_pch should not be called in generic PC
> code.
>

I track this path:

qemu_register_pc_machine(&xenfv_machine);
	|
	+ .init = pc_xen_hvm_init,
		|
		+ pc_init_pci(machine);
			|
			+ pc_init1(machine, 1, 1);
				|
				+ i440fx_init()

So how to separate this to specific to xen? Or you mean we need to 
create an new machine to address this scenario? But actually this is 
same as xenfv_machine except for these little codes.

If you don't like this involve other cases, we may drop this chunk of 
codes as a function to tweak with CONFIG_XEN. But this is not good as 
well since this is device feature, so kvm may need this one day.


Thanks
Tiejun