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Date: Fri, 28 Aug 2009 10:08:32 +0530
From: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
To: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>, Ingo Molnar <mingo@elte.hu>,
       lkml <linux-kernel@vger.kernel.org>,
       systemtap <systemtap@sources.redhat.com>,
       DLE <dle-develop@lists.sourceforge.net>
Subject: Re: [PATCH -tip tracing/kprobes 1/6] kprobes/x86: Call BUG() when
	reentering probe into KPROBES_HIT_SS
Message-ID: <20090828043832.GC7220@in.ibm.com>
Reply-To: ananth@in.ibm.com
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On Thu, Aug 27, 2009 at 01:22:58PM -0400, Masami Hiramatsu wrote:
> Call BUG() when a probe have been hit on the way of kprobe processing path,
> because that kind of probes are currently unrecoverable (recovering it will
> cause an infinit loop and stack overflow).
> 
> The original code seems to assume that it will be caused by an int3 which
> another subsystem inserted on out-of-line singlestep buffer if the hitting
> probe is same as current probe. However, in that case, int3-hitting-address
> is on the out-of-line buffer and should be different from first (current)
> int3 address.
> Thus, I decided to remove the code.
> 
> I also removes arch_disarm_kprobe() because it will involve other stuffs
> in text_poke().
> 
> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
> Cc: Frederic Weisbecker <fweisbec@gmail.com>
> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
> Cc: Ingo Molnar <mingo@elte.hu>

Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>