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Date: Tue, 26 Feb 2008 22:51:12 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Dan Upton <upton.dan.linux@gmail.com>
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Subject: Re: rdmsr_safe_on_cpu hangs?
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Dan Upton wrote:
> 
> I guess the question is, am I just misunderstanding the use of
> rdmsr_safe_on_cpu, or is it an issue with that particular MSR (some of
> the stuff I've read indicates that rdmsr_safe was really only
> implemented as a prequel to the coretemp driver), or is it something
> wrong with rdmsr_safe_on_cpu?
> 

*msr_safe_*() can only trap #GP's, which would be manifest as oopses if 
you used the unsafe versions.  If the CPU *hangs* when touching an MSR, 
nothing we can do in software will help.

	-hpa