Joerg Roedel wrote:
> Hello,
> 
> yesterday I tried to reactivate my old 486 box and wanted to install a
> current Linux with latest kernel on it. But it turned out that the
> latest kernel does not boot because the machine crashes early in the
> setup code.
> After some debugging it turned out that the problem is the query_ist()
> function. If this interrupt with that function is called the machine
> simply locks up. It looks like a BIOS bug. Looking for a workaround for
> this problem I wrote the attached patch. It checks for the CPUID
> instruction and if it is not implemented it does not call the speedstep
> BIOS function. As far as I know speedstep should be available since some
> Pentium earliest.
> Is this an acceptable workaround or is there a better one for this?
> 
> Regards,
> 
> Joerg

Right in concept, but I dislike the implementation (duplication of the 
CPU detect code we already have).  Could you try this patch and see if 
it works for you?

	-hpa