From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH] Revert "x86: Disable IST stacks for debug/int 3/stack
 fault for PREEMPT_RT"
Date: Sat, 4 Jan 2014 19:18:07 +0100
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Cc: Ben Hutchings <ben@decadent.org.uk>,
	Thomas Gleixner <tglx@linutronix.de>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	Steven Rostedt <rostedt@rostedt.homelinux.com>,
	723180@bugs.debian.org, Brian Silverman <bsilver16384@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>,
	linux-rt-users@vger.kernel.org, Andi Kleen <andi@firstfloor.org>
To: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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On Fri, Jan 03, 2014 at 02:55:48PM +0100, Sebastian Andrzej Siewior wrote:
> where do I start. Let me explain what is going on here. The code
> sequence

Yes the IST stacks are needed for correctness, even in more cases than
the example below. You cannot just disable them, just because you don't
like them.

-Andi