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Date: Tue, 18 Nov 2008 04:53:05 -0500
From: Christoph Hellwig <hch@infradead.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: Large stack usage in fs code (especially for PPC64)
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Cc: Thomas Gleixner <tglx@linutronix.de>, LKML <linux-kernel@vger.kernel.org>,
	Steven Rostedt <rostedt@goodmis.org>, linuxppc-dev@ozlabs.org,
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On Tue, Nov 18, 2008 at 10:03:25AM +1100, Benjamin Herrenschmidt wrote:
> On Mon, 2008-11-17 at 15:34 -0500, Steven Rostedt wrote:
> > Note, I was using a default config that had CONFIG_IRQSTACKS off and
> > CONFIG_PPC_64K_PAGES on.
> 
> For one, we definitely need to turn IRQSTACKS on by default ... In fact,
> I'm pondering just removing the option.

It shouldn't be a user-visible option.  It shouldn't on x86 either, but
there it always gets into the ideological 4k stacks flameware so people
usually gave up after a while instead of doing the sensibke 8k +
irqstacks by default, 4k as an option..