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Date: Mon, 16 Jul 2007 15:53:29 -0700
From: "Ray Lee" <ray-lk@madrabbit.org>
To: "Alan Cox" <alan@lxorguk.ukuu.org.uk>
Subject: Re: [PATCH][RFC] 4K stacks default, not a debug thing any more...?
Cc: "Rene Herman" <rene.herman@gmail.com>, "Bodo Eggert" <7eggert@gmx.de>,
       "Matt Mackall" <mpm@selenic.com>,
       "Jeremy Fitzhardinge" <jeremy@goop.org>,
       "Jesper Juhl" <jesper.juhl@gmail.com>,
       "Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
       "William Lee Irwin III" <wli@holomorphy.com>,
       "David Chinner" <dgc@sgi.com>, "Arjan van de Ven" <arjan@infradead.org>
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On 7/16/07, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> > If at some point one of the pro-4k stacks crowd can prove that all
> > code paths are safe, or introduce another viable alternative (such as
> > Matt's idea for extending the stack dynamically), then removing the 8k
> > stacks option makes sense.
>
> Any x86-32 path unsafe with 4K stacks is almost certainly unsafe with 8K
> stacks because the 8K stacks do not have seperate IRQ stack paths, so you
> have the same space but split. It might be less predictable on 8K stacks
> but it isn't absent.

Understood, but isn't that an argument pro interrupt stacks, rather
than one against 8k? wli has a patch to break out the interrupt stack
feature from the 4k/8k choice.