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Date: Tue, 15 May 2012 16:31:42 +0800
From: Cong Wang <xiyou.wangcong@gmail.com>
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To: Namhyung Kim <namhyung.kim@lge.com>
CC: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        linux-kernel@vger.kernel.org, Hyeoncheol Lee <cheol.lee@lge.com>
Subject: Re: [QUESTION] Kprobes as a module?
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On 05/15/2012 04:24 PM, Namhyung Kim wrote:
> Hi,
>
> Probably a dumb question :).
> What prevents the kprobes from being built as a module? We want to use
> the kprobes on our systems, but some guys worried about potential
> security problems. So it'd be great if we can enable/load kprobes as
> needed and then disable/unload after using it. Is it a possible senario?
>

Kconfig prevents that:

config KPROBES
         bool "Kprobes"
         depends on MODULES
         depends on HAVE_KPROBES
         select KALLSYMS


so you can have either CONFIG_KPROBES=y or CONFIG_KPROBES=n, but not =m.