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Date: Tue, 29 Jan 2002 15:36:57 -0800 (PST)
From: Linus Torvalds <torvalds@transmeta.com>
To: Oliver Xymoron <oxymoron@waste.org>
cc: Rusty Russell <rusty@rustcorp.com.au>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] per-cpu areas for 2.5.3-pre6
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On Tue, 29 Jan 2002, Oliver Xymoron wrote:
>
> Seems like we could do slightly better to have these local areas mapped to
> the same virtual address on each processor, which does away with the need
> for an entire level of indirection.

No no no.

That is a really stupid idea, even though every single OS developer has at
some time thought that it was the great idea (and it shows up in a lot of
OS's).

The reason it is a stupid idea is that if you do it, you can no longer
share page tables between CPU's (unless all CPU's you support have TLB
fill in software).

		Linus

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