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Date: Tue, 24 Nov 2009 16:42:00 -0000
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Masami Hiramatsu <mhiramat@redhat.com>
CC: Frederic Weisbecker <fweisbec@gmail.com>, Ingo Molnar <mingo@elte.hu>,         Ananth N Mavinakayanahalli <ananth@in.ibm.com>,         lkml <linux-kernel@vger.kernel.org>,         systemtap <systemtap@sources.redhat.com>,         DLE <dle-develop@lists.sourceforge.net>,         Jim Keniston <jkenisto@us.ibm.com>,         Srikar Dronamraju <srikar@linux.vnet.ibm.com>,         Christoph Hellwig <hch@infradead.org>,         Steven Rostedt <rostedt@goodmis.org>,         Anders Kaseorg <andersk@ksplice.com>, Tim Abbott <tabbott@ksplice.com>,         Andi Kleen <andi@firstfloor.org>, Jason Baron <jbaron@redhat.com>,         Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Subject: Re: [PATCH -tip v5 07/10] kprobes/x86: Support kprobes jump optimization  on x86
References: <20091123232115.22071.71558.stgit@dhcp-100-2-132.bos.redhat.com> <20091123232211.22071.58974.stgit@dhcp-100-2-132.bos.redhat.com>
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On 11/23/2009 03:22 PM, Masami Hiramatsu wrote:
> 
> This uses stop_machine() for corss modifying code from int3 to jump.
> It doesn't allow us to modify code on NMI/SMI path. However, since
> kprobes itself doesn't support NMI/SMI code probing, it's not a
> problem.
> 

I'm a bit confused by the above statement... does that mean you're
poking int3 and *then* do stop_machine()?

	-hpa

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