From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH] kvm: bios: Put AP boot up code to 0x1000
Date: Fri, 01 Aug 2008 08:49:14 -0700
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References: <200807311043.20880.sheng.yang@intel.com> <200807311400.11644.sheng.yang@intel.com> <48915E80.8010406@qumranet.com> <200807311709.29198.sheng.yang@intel.com> <489189E0.8070804@qumranet.com>
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Cc: "Yang, Sheng" <sheng.yang@intel.com>, kvm@vger.kernel.org
To: Avi Kivity <avi@qumranet.com>
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Avi Kivity wrote:
> 
> IIRC the rombios32.c writes to the memory it is in, so it expects RAM, 
> not ROM.
> 
> kvm doesn't support ROM, so it would work.  Qemu doesn't, so it would fail.
> 

You can specify either RAM or ROM in Qemu, but you have to edit the C code.

If you need RAM in the low 640K, your choices are roughly 0x300..0x340 
or in the EBDA.

	-hpa