Re: [PATCH 1/2] x86: mce init optimization and signedness fixup

From: Thomas Gleixner
Date: Thu Oct 11 2007 - 10:55:56 EST


On Thu, 11 Oct 2007, Christoph Egger wrote:

> On Thursday 11 October 2007 15:51:49 Thomas Gleixner wrote:
> > On Thu, 11 Oct 2007, Joerg Roedel wrote:
> > > MCG_CAP never reports a negative count of available error-reporting
> > > banks. Therefore, make nr_mce_banks unsigned.
> > > Check for MCA/MCE feature bits as early as possible.
> > >
> > > +
> > > + if (!cpu_has(c, X86_FEATURE_MCA) || !cpu_has(c, X86_FEATURE_MCE)) {
> > > + printk(KERN_INFO "CPU%i: No machine check support available\n",
> > > + smp_processor_id());
> > > + return;
> >
> > This breaks winchip MCE support.
>
> First, what is a winchip? It sounds to be something windows specific. ;)
> Second, can you explain in which way MCE support gets broken, please?

First, winchip is the code name of Centaurs early x86 cpus.

Second, those beasts do not have FEATURE_MCA, but they have FEATURE_MCE,
so they support the fatal exception, but not the non fatal check.

tglx
-
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/