On Tue, Feb 14, 2012 at 01:10:59PM +0200, Pekka Enberg wrote: > On Tue, Feb 14, 2012 at 1:03 PM, Yang Bai <hamo.by@xxxxxxxxx> wrote: > > Since on X86, bios is always at the end of the address space, so I > > have some thought about how to implement the seabios support for kvm > > tool. > > > > 1. using kvm__register_mem to map the end of address space to the > > guest then copy the code of seabios to this mem region. Just emulating > > the bios chip. I think this is what should be done. > > > > 2. leave the bios code alone and don't touch the guest's address > > space. If the guest accesses the address belonging to the bios, it > > will be an IO request and we can emulate the IO access to the bios > > chip. > > > > Any ideas about this? > > The latter solution doesn't make any sense to me. Cyrill, do we really > need to put the BIOS at the end of the address space? Don't we have > unused space below 1 MB? I don't remember for sure how SeaBIOS works actually. What I rememer is that it aquires all hw environment might have. So without real look into seabios code I fear I can't answer. But reserving end of 4G address space for bios copy sounds reasonable if we going to behave as real hardware. Maybe we could poke someone from KVM camp for a hint? Cyrill -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
