Re: [patches] Re: [PATCH] [14/19] i386: Disable nmi watchdog on all ThinkPads

From: Dave Jones
Date: Sat Oct 21 2006 - 14:15:10 EST


On Sat, Oct 21, 2006 at 08:11:56PM +0200, Andi Kleen wrote:
>
> > > - if (nmi_watchdog == NMI_DEFAULT && dmi_get_year(DMI_BIOS_DATE) >= 2004)
> > > + Probably safe on most older systems too, but let's be careful.
> > > + IBM ThinkPads use INT10 inside SMM and that allows early NMI inside SMM
> > > + which hangs the system. Disable watchdog for all thinkpads */
> > > + if (nmi_watchdog == NMI_DEFAULT && dmi_get_year(DMI_BIOS_DATE) >= 2004 &&
> > > + !dmi_name_in_vendors("ThinkPad"))
> > > nmi_watchdog = NMI_LOCAL_APIC;
> >
> > This is going to get some people scratching their heads wondering
> > why it isn't working if they ever try nmi_watchdog on one of these.
> > How about adding an explanitory printk ?
>
> When you enable it manually then NMI_DEFAULT won't be set and this code
> is never executed.
>
> BTW their machines will likely not stay up long enough that they can
> see the printk (unless Lenovo fixes that particular bug in the future,
> they are aware of it)

Ouch, nasty. I'm surprised no-one complained about this earlier.

Dave


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