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Date: Wed, 05 Jul 2006 09:38:56 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Andi Kleen <ak@suse.de>
CC: Chuck Ebbert <76306.1226@compuserve.com>, Andrew Morton <akpm@osdl.org>,
       Ingo Molnar <mingo@elte.hu>, Linus Torvalds <torvalds@osdl.org>,
       linux-kernel@vger.kernel.org
Subject: Re: [patch] i386: early pagefault handler
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Andi Kleen wrote:
> 
>> +hlt_loop:
>> +	hlt
> 
> There are still supported i386 CPUs that don't support HLT and
> would recursively fault here.
> 

The HLT has been supported since 8086.  However, it was broken in some 
early 486s (not 386s); that's what the test in the kernel is for.

I don't remember what the failure mode was, though; didn't think it was 
recursive faulting.

	-hpa