Re: [Qemu-devel] [PATCH 0/2 v2] pc: inform SeaBIOS where 64-bit PCI hole begins

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 04 Nov 2013 13:48:03 +0100
Gerd Hoffmann <kraxel@redhat.com> wrote:

>   Hi,
> 
> > > So maybe design that with memory hotplug in mind?  Such as adding a new
> > > qemu-specific type QEMU_RAM_HOTPLUG?  Which seabios could use to reserve
> > > the memory (but not add it to the e820 table for the guest)?
> > It will do job too. But extending semantics of standard table would be
> > confusing. Yes, Seabios will filter it out but it doesn't make table
> > less confusing.
> 
> Was just thinking that it might be easier that way if we need e820
> entries for hotplug memory address space _anyway_.
I don't think that we need e820 entries for hotplug memory reserved space as
e820 should. In case present at boot hotpluggable DIMMs would be needed in E820,
we can add them as usual E820_RAM entries.

But regardless of what we do here it might be good keep option of adding non
standard entries in future, by filtering out unknown types in SeaBIOS.

> 
> > I'd prefer having a dedicated interface for it as a more clean solution.
> 
> Agree.

So back to naming question, would you agree to renaming fw_cfg to the last
Michael's suggestion "reserved-memory-end"?
 
> cheers,
>   Gerd
> 
> 
>