Re: [Qemu-devel] Re: [PATCH 2/3] qemu: make cirrus init value pci spec compliant

[Gleb Natapov]

On Mon, Oct 12, 2009 at 04:50:35PM +0200, Gerd Hoffmann wrote:
> On 10/12/09 15:53, Gleb Natapov wrote:
> >On Mon, Oct 12, 2009 at 03:45:47PM +0200, Gerd Hoffmann wrote:
> >>>>>>We should fix qemu to re-read bios from flash.
> >>>>>>Makes sense?
> >>>>>>
> >>>>>We have option_rom_setup_reset() already.
> >>>>
> >>>>We don't, anymore :)
> >>>We are fast! Well, we surely have something similar instead.
> >>
> >>Sure.  Try 'info roms'.  Everything listed there will be reloaded on
> >>reset (unless mem=rom, in which case the guest should not be able to
> >>modify the bits in the first place).  That includes vgabios,
> >>optionroms, -kernel images, ...
> >>
> >And what about bios? I don't see it there.
> 
> pc.c does some magic here to map the complete bios into high memory
> and the legacy part at 0xe0000, thats why it is loaded in a
> different way. It gets loaded to IO_MEM_ROM memory though, so the
> guest should not be able to corrupt it.
> 
But KVM doesn't support it (memory is always writable). And we want to reload
BIOS on reboot for migration purposes.

--
                        Gleb.