Re: Fail to early boot with v2.6.27-rc2 to at least v2.6.29-rc2 due to dc1e35c

From: Suresh Siddha
Date: Mon Jan 19 2009 - 16:57:48 EST


On Mon, Jan 19, 2009 at 01:46:37PM -0800, Avuton Olrich wrote:
> On Mon, Jan 19, 2009 at 12:11 PM, Suresh Siddha
> <suresh.b.siddha@xxxxxxxxx> wrote:
> > Avuton, Does your bios has an option which says limit the cpuid
> > vector limit to '2' or something. Can you disable that option and
> > re-check? It will typically be located under cpu configuration settings.
>
> You're the winner of the prize. The culprit in my bios was:
>
> Max CPUID Value Limit: Enabled

Though the bios is the culprit and this option will severely limit
the cpu capabilities that OS can take advantage of, OS should fallback
to a safer mode. I will have a patch for it.

Also, I wonder, if we should complain/scream during boot if we find only
fewer cpuid levels on modern generation cpu's.

thanks,
suresh
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/