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Date: Sat, 19 Apr 2008 16:23:29 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Arjan van de Ven <arjan@infradead.org>,
       Thomas Gleixner <tglx@linutronix.de>
Subject: Re: x86: 4kstacks default
Message-ID: <20080419142329.GA5339@elte.hu>
References: <200804181737.m3IHbabI010051@hera.kernel.org> <20080418142934.38ce6bf4.akpm@linux-foundation.org>
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* Andrew Morton <akpm@linux-foundation.org> wrote:

> >  config 4KSTACKS
> >  	bool "Use 4Kb for kernel stacks instead of 8Kb"
> > -	depends on DEBUG_KERNEL
> >  	depends on X86_32
> > +	default y
> 
> This patch will cause kernels to crash.

what mainline kernels crash and how will they crash? Fedora and other 
distros have had 4K stacks enabled for years:

  $ grep 4K /boot/config-2.6.24-9.fc9
  CONFIG_4KSTACKS=y

and we've conducted tens of thousands of bootup tests with all sorts of 
drivers and kernel options enabled and have yet to see a single crash 
due to 4K stacks. So basically the kernel default just follows the 
common distro default now. (distros and users can still disable it)

	Ingo