Re: Proper support for PCI-based option rom loading (was Re: [Qemu-devel] Re: qdev property bug?)

[Anthony Liguori]

Michael S. Tsirkin wrote:
> > I think it's stable-0.12 material because it's badly broken right now  
> >     
>
> I thought the rule was no guest visible changes in stable series?
>   

Yeah, good point, so we need to figure out something for 0.12.0.

Sebastian's suggestion of loading roms from 0xc0000 first and then from 
PCI devices is a good one, but I think the problem with that is that the 
roms don't necessarily have to be contiguous in that space.  For 
instance, the lower bios portions are technically in the rom area which 
leaves a big gap in the middle.

We could just assume that knowledge in SeaBIOS.

We'll also need the ability to select whether to use PCI or legacy rom 
loading for each PCI device (via a qdev property).  This will need to be 
plumbed into the machine compat bits such that -M pc-0.11.0 uses legacy 
rom loading.  Otherwise, the PCI devices will be detectably different 
within the guest.

Regards,

Anthony Liguori