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Date: Mon, 28 Jul 2008 09:45:20 -0400
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Ingo Molnar <mingo@elte.hu>
CC: Jan Beulich <jbeulich@novell.com>, Andi Kleen <andi@firstfloor.org>,
       tglx@linutronix.de, linux-kernel@vger.kernel.org,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Joerg Roedel <joro@8bytes.org>
Subject: Re: [PATCH] i386: improve double fault handling
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Ingo Molnar wrote:
> 
> Secondly, task gates are really a relic that should not be proliferated. 
> Besides the complications in virtualized environments (if more common 
> things like Big Real Mode are not supported well in virtual mode what do 
> we expect of more esoteric features as task gates?) it does not get 
> nearly as much testing on real silicon as other, more mainstream CPU 
> features.
> 

I think that using it as a bailout mechanism is going to remain 
supported and tested.  It's just never going to be fast.

	-hpa