Re: [PATCH 2.6.24] x86: add sysfs interface for cpuid module

[H. Peter Anvin]

Yi Yang wrote:
> > It's broken, because it doesn't take into account the fact that Intel 
> > broke CPUID level 4 and made it "repeating" (neither did the cpuid char 
> > device, because it predated the Intel braindamage; I've had a patch for 
> > it privately for a while, but didn't push it upstream because paravirt 
> > broke it royally and I wanted the situation to settle down.)

> level 4 doesn't result in repeating on Intel CPU, cpuid module sets
> file offset to level, so cat /dev/cpu/*/cpuid will run cpuid instruction
> continuously.

The issue is that Intel suddenly made CPUID ECX-sensitive, which there 
is no way to represent.

As far as cat /dev/cpu/*/cpuid, that's a user error.

	-hpa

--
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/