From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
To: Ingo Molnar <mingo@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
Sandeepa Prabhu <sandeepa.prabhu@linaro.org>,
x86@kernel.org, lkml <linux-kernel@vger.kernel.org>,
"Steven Rostedt (Red Hat)" <rostedt@goodmis.org>,
systemtap@sourceware.org, "David S. Miller" <davem@davemloft.net>
Subject: Re: Re: Re: [PATCH -tip v4 0/6] kprobes: introduce NOKPROBE_SYMBOL() and fixes crash bugs
Date: Fri, 13 Dec 2013 06:06:00 -0000 [thread overview]
Message-ID: <52AAA3CE.9010301@hitachi.com> (raw)
In-Reply-To: <52AA9C55.1000103@hitachi.com>
(2013/12/13 14:34), Masami Hiramatsu wrote:
>> Lets assume we allow a probe to be inserted in the single-step path.
>> Such a probe will be an INT3 instruction and if it hits we get a
>> recursive INT3 invocation. In that case the INT3 handler should simply
>> restore the original instruction and _leave it so_. There's no
>> single-stepping needed - the probe is confused and must be discarded.
>
> But how can we restore the protected kernel text?
> If we use text_poke, we also need to prohibit probing on the text_poke
> and functions called in the text_poke too. That just shifts the annotated
> area to the text_poke. :(
BTW, currently we mark the text_poke as nokprobe_symbol, but it should be
removed. We don't call it from kprobes int3/debug handlers.
The patches which removes __kprobes in this series are only for kprobe
related files (arch/x86/kernel/kprobes/* or kernel/kprobes.c.) I think
we should do it for other parts.
Is it better to do that on this series?
Thank you,
--
Masami HIRAMATSU
IT Management Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com
next prev parent reply other threads:[~2013-12-13 6:06 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-04 1:34 Masami Hiramatsu
2013-12-04 1:34 ` [PATCH -tip v4 1/6] kprobes: Prohibit probing on .entry.text code Masami Hiramatsu
2013-12-04 1:35 ` [PATCH -tip v4 2/6] kprobes: Introduce NOKPROBE_SYMBOL() macro for blacklist Masami Hiramatsu
2013-12-04 1:36 ` [PATCH -tip v4 3/6] [BUGFIX] kprobes/x86: Prohibit probing on debug_stack_* Masami Hiramatsu
2013-12-04 1:36 ` [PATCH -tip v4 4/6] [BUGFIX] x86: Prohibit probing on native_set_debugreg Masami Hiramatsu
2013-12-04 1:36 ` [PATCH -tip v4 6/6] [RFC] kprobes/x86: Call exception handlers directly from do_int3/do_debug Masami Hiramatsu
2013-12-04 2:39 ` Steven Rostedt
2013-12-11 13:31 ` Jiri Kosina
2013-12-12 4:40 ` Masami Hiramatsu
2013-12-12 9:59 ` Jiri Kosina
2013-12-12 10:31 ` Masami Hiramatsu
2013-12-04 1:36 ` [PATCH -tip v4 5/6] [BUGFIX] x86: Prohibit probing on thunk functions and restore Masami Hiramatsu
2013-12-04 2:54 ` [PATCH -tip v4 0/6] kprobes: introduce NOKPROBE_SYMBOL() and fixes crash bugs Sandeepa Prabhu
2013-12-04 7:39 ` Masami Hiramatsu
2013-12-04 8:46 ` Sandeepa Prabhu
2013-12-04 23:32 ` Masami Hiramatsu
2013-12-04 8:46 ` Ingo Molnar
2013-12-04 23:28 ` Masami Hiramatsu
2013-12-05 10:21 ` Ingo Molnar
2013-12-06 2:34 ` Masami Hiramatsu
2013-12-10 15:28 ` Ingo Molnar
2013-12-11 2:12 ` Masami Hiramatsu
2013-12-11 13:34 ` Ingo Molnar
2013-12-12 6:02 ` Masami Hiramatsu
2013-12-12 14:03 ` Ingo Molnar
2013-12-12 20:42 ` Josh Stone
2013-12-13 5:34 ` Masami Hiramatsu
2013-12-13 6:06 ` Masami Hiramatsu [this message]
2013-12-16 10:53 ` Masami Hiramatsu
2013-12-05 13:08 ` Sandeepa Prabhu
2013-12-06 6:23 ` Masami Hiramatsu
2013-12-06 6:54 ` Sandeepa Prabhu
2013-12-06 23:26 ` Masami Hiramatsu
2013-12-05 14:49 ` Frank Ch. Eigler
2013-12-06 6:13 ` Masami Hiramatsu
2013-12-06 19:08 ` Frank Ch. Eigler
2013-12-06 23:19 ` Masami Hiramatsu
2013-12-07 1:33 ` Frank Ch. Eigler
2013-12-07 2:35 ` Masami Hiramatsu
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