Date: Tue, 12 Jan 2010 08:06:00 -0800
From: Arjan van de Ven <arjan@infradead.org>
To: Dongdong Deng <libfetion@gmail.com>
Cc: linux-kernel@vger.kernel.org, ananth@in.ibm.com,
       anil.s.keshavamurthy@intel.com, davem@davemloft.net,
       mhiramat@redhat.com, jkenisto@us.ibm.com
Subject: Re: Did we really need to clear the IF flag at prepare_singlestep()
 of  x86 kprobes?
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References: <ce2c83091001120309q19d58b45kc27610fc31ce01dc@mail.gmail.com>
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On Tue, 12 Jan 2010 19:09:35 +0800
Dongdong Deng <libfetion@gmail.com> wrote:

> Hi Kprobe experts,
> 
> I have a doubt about the handling "X86_EFLAGS_IF" at
> prepare_singlestep(), Could you give me some suggestions?


iirc it was a security thing; we used to have some exploits
due to the linux-abi entry points which caused a mess, and this
was put there as defensive programming.

I could totally misremember this as well of course.


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org
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