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From: Bart Trojanowski <bart@jukie.net>
To: fastboot@lists.osdl.org
Cc: linux-kernel@vger.kernel.org
Subject: restoring x86 BIOS state before reboot
Date: Fri, 6 Apr 2007 11:46:28 -0400	[thread overview]
Message-ID: <20070406154628.GG12005@jukie.net> (raw)

Hi all,

I am looking at a two stage boot where linux is loaded to do some system
initialization before booting to Windows, which needs BIOS.

I am interested in bypassing the BIOS on the second boot.

I wanted to know if anyone has attempted to restore the BIOS memory such 
that this could be attempted.  If not, I would love to get some pointers
:)

My plan right now is to backup the 128k of memory under 0x10000 to some
staging memory under 0x90000, temporarily while in real mode, and then
move it up somewhere higher once the kernel is running.

Then on reboot I hope to undo the above and jump to 0x00007c00.

Does this approach have any merit?

Cheers,

-Bart

             reply	other threads:[~2007-04-06 17:05 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-04-06 15:46 Bart Trojanowski [this message]
2007-04-06 17:48 ` restoring x86 BIOS state before reboot Jan Engelhardt
2007-04-29  6:51 ` [Fastboot] " Eric W. Biederman
2007-04-29  9:41   ` Bernhard Walle
2007-04-29 14:46     ` Eric W. Biederman
2007-04-29 16:28     ` David Woodhouse
2007-05-11 18:23     ` Pavel Machek
2007-05-11 19:29       ` Jeremy Fitzhardinge
2007-05-11 20:18       ` H. Peter Anvin
2007-05-11 21:11         ` yhlu

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