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Date: Fri, 31 May 2013 14:48:17 +0200
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Subject: Re: [Qemu-devel] [PATCH v7 1/4] isapc: Fix non-KVM qemu boot
 (read/write memory for isapc BIOS)
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To: Kevin O'Connor <kevin@koconnor.net>
Cc: Jordan Justen <jordan.l.justen@intel.com>, qemu-devel@nongnu.org

Il 31/05/2013 04:06, Kevin O'Connor ha scritto:
> On Wed, May 29, 2013 at 01:27:24AM -0700, Jordan Justen wrote:
>> > The isapc machine with seabios currently requires the BIOS region
>> > to be read/write memory rather than read-only memory.
>> > 
>> > KVM currently cannot support the BIOS as a ROM region, but qemu
>> > in non-KVM mode can. Based on this, isapc machine currently only
>> > works with KVM.
>> > 
>> > To work-around this isapc issue, this change avoids marking the
>> > BIOS as readonly for isapc.
> How about changing the code to always make the ROM read/write (instead
> of doing it only on isapc).  Currently, if the rom is marked as
> read-only, then SeaBIOS makes it read/write as the first thing it
> does.  So, making it read-only doesn't really serve any purpose.

I don't think SeaBIOS can rely on the value of the PAM registers when it
is started via a CPU reset (INIT), can it?

Paolo