On 12.06.13 at 16:02, Paolo Bonzini <address@hidden> wrote:
Il 12/06/2013 09:49, Jan Beulich ha scritto:
#3 should be possible or even the default (would need to check), but #4
is probably a bit harder to do. Perhaps you can use a magic I/O port
for the xen platform PV driver, but if you can simply use two PCI
windows it would be much simpler because that's the same that TCG and
KVM already do. The code is all there for you to lift in SeaBIOS.
What is the connection here to the platform PV driver?
It's just a hook you already have for Xen-specific stuff in QEMU.
Oh, sorry, I'm generally taking this term to refer to a Linux
component.
Only Windows XP and older had problems with that because they didn't
like something in the ASL; but the 64-bit window is placed at the end of
RAM, so in principle any PAE-enabled OS can use it.
At the end of _RAM_???
Why the question marks? :)
Ah, so mean right after RAM. "At the end of RAM" reads like
overlapping (and discarding) the tail of it.
If you have 4GB of RAM it will end at 0x140000000 (or something like
that) and that's where the 64-bit window starts. Of course if you have
no RAM above the PCI hole, the 64-bit window will start at 0x100000000.
So there's no provision whatsoever for extending the amount of RAM
a guest may see? This is why I'd see any such allocation strategy to
start at the end of physical address space, moving downwards.