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Date: Sat, 31 Jan 2009 01:54:45 +0100
From: Ingo Molnar <mingo@elte.hu>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>, Tejun Heo <tj@kernel.org>,
       paulmck@linux.vnet.ibm.com,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Yinghai Lu <yinghai@kernel.org>, Thomas Gleixner <tglx@linutronix.de>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>,
       Brian Gerst <brgerst@gmail.com>
Subject: Re: Seeing "huh, entered softirq 8 ffffffff802682aa preempt_count
	00000100, exited with 00010100?" in tip.git
Message-ID: <20090131005445.GB21022@elte.hu>
References: <498229CF.1090007@goop.org> <20090130005953.GD6716@linux.vnet.ibm.com> <49825B8B.2000202@goop.org> <20090130150859.GB27549@elte.hu> <20090130221747.GA6877@elte.hu> <20090130223455.GA4151@elte.hu> <49839FCB.3010509@goop.org> <4983A00F.5040505@zytor.com>
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* H. Peter Anvin <hpa@zytor.com> wrote:

> Jeremy Fitzhardinge wrote:
>>
>> I found my bug.  Turns out all my CPUs were sharing the same kernel  
>> stack (!), which means it was working surprisingly well, considering...
>>
>
> ROTFLMAO!

muhaha. I wrote such a bug only once in my whole life - back when we wrote 
the first version of the Linux SMP code, more than a decade ago. It was a 
lot of fun to debug - the exact point and nature of the crash changed as i 
added printks to the bootup code ;-)

	Ingo