Re: overriding BIOS (was: Re: [ANNOUNCE] kvm howto)

From: Arjan van de Ven
Date: Mon Nov 13 2006 - 15:39:30 EST


On Mon, 2006-11-13 at 21:34 +0100, Tomasz Torcz wrote:
> On Mon, Nov 06, 2006 at 12:15:02AM -0800, Dor Laor wrote:
> > The BIOS check is a must, it checks bit #0 of MSR_IA32_FEATURE_CONTROL,
> > if it set this means that software cannot write to the MSR. If bit #2 is
> > clear too then when executing vmxon you'll get #GP.
> >
> > So the check should better be there...
>
> You were right, just writing to this MSR (via kvm_enable) halts my laptop.
> Which is kinda strange, as this solution works on Intel Mac Minis.
>
> Anyway, complaint to Lenovo sent and got ignored.
>

the linux-ready firmware developer kit now tries to test for this; with
some luck the bios people will run this and fix it ;)

--
if you want to mail me at work (you don't), use arjan (at) linux.intel.com
Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org

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