From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: qemu oddness with isolinux vesamenu.c32
Date: Sat, 19 Jul 2008 11:29:56 -0700
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Cc: Matt_Domsch@Dell.com, pjones@redhat.com, kvm@vger.kernel.org,
	Anthony Liguori <aliguori@us.ibm.com>
To: Avi Kivity <avi@qumranet.com>
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Avi Kivity wrote:
> 
> kvm allows writing into the bios; qemu does not.  I thought it was a kvm 
> bug, but turns out that it's a qemu bug...
> 
> (though to be fair, true emulation ought to start out read-only, then be 
> enabled by the bios ram shadow mechanism)
> 

Yes, although simulating the memory "pre-shadowed" works just as well; 
then it should be marked readonly by the BIOS immediately prior to 
running INT 19h.

	-hpa