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Date: Wed, 26 Aug 2009 10:24:03 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Peter Zijlstra <peterz@infradead.org>
CC: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
       Frederic Weisbecker <fweisbec@gmail.com>,
       Hendrik Brueckner <brueckner@linux.vnet.ibm.com>,
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       jiayingz@google.com, mbligh@google.com, lizf@cn.fujitsu.com,
       Heiko Carstens <heiko.carstens@de.ibm.com>,
       Martin Schwidefsky <schwidefsky@de.ibm.com>,
       Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH 08/12] add trace events for each syscall entry/exit
References: <20090825141547.GE6114@nowhere>	 <20090825160237.GG4639@cetus.boeblingen.de.ibm.com>	 <20090825162004.GA25058@Krystal> <20090825165912.GI6114@nowhere>	 <20090825173107.GJ6114@nowhere>  <20090825183119.GC2448@Krystal> <1251270602.7538.1228.camel@twins>
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On 08/26/2009 12:10 AM, Peter Zijlstra wrote:
> On Tue, 2009-08-25 at 14:31 -0400, Mathieu Desnoyers wrote:
>> For instance, some
>> proprietary Linux driver does very odd things with system calls within
>> kernel threads, like invoking them with int 0x80.
> 
> So who is going to send the x86 patch to make int 0x80 from kernel space
> panic the machine? :-)

Panicing might be a pretty darn good idea, since $DEITY knows what state
your stacks are in at that point, and if it is about to overflow.

... besides all the other evilness that entails.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.