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Date: Tue, 19 Aug 2008 16:58:46 -0700
From: Jeremy Fitzhardinge <jeremy@goop.org>
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To: benh@kernel.crashing.org
Subject: Re: ftrace introduces instability into kernel 2.6.27(-rc2,-rc3)
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Cc: Nick Piggin <nickpiggin@yahoo.com.au>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
	linux-kernel@vger.kernel.org,
	Steven Rostedt <rostedt@goodmis.org>, linuxppc-dev@ozlabs.org,
	Steven Rostedt <srostedt@redhat.com>, Scott Wood <scottwood@freescale.com>,
	Eran Liberty <liberty@extricom.com>
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Benjamin Herrenschmidt wrote:
>> Ok, there are two cases where it's ok :
>>
>> 1 - in stop_machine, considering we are not touching code executed in
>> NMI handlers.
>> 2 - when using my replace_instruction_safe() which uses a temporary
>> breakpoint when doing the instruction replacement.
>>
>> In those cases you could use text_poke_early().
>>     
>
> Note that vmap/vunmap will be very slow.
>   

Don't we have Nick's speedups now?

    J