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From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: "H. Peter Anvin" <hpa@linux.intel.com>,
	Jiri Kosina <jkosina@suse.cz>, Jason Baron <jbaron@redhat.com>,
	Borislav Petkov <bpetkov@suse.de>,
	linux-kernel@vger.kernel.org
Subject: Re: [RFC] [PATCH 1/2 v2] x86: introduce int3-based instruction patching
Date: Fri, 12 Jul 2013 10:00:42 +0900	[thread overview]
Message-ID: <51DF553A.6010108@hitachi.com> (raw)
In-Reply-To: <1373561176.17876.44.camel@gandalf.local.home>

(2013/07/12 1:46), Steven Rostedt wrote:
> On Thu, 2013-07-11 at 09:31 -0700, H. Peter Anvin wrote:
> 
>> The current code assumes that one of the two code sequences is a NOP,
>> and therefore that jumping over the region is legal.  This does not
>> allow for transitioning one active code sequence to another.
> 
> Correct, and I think we should keep the two changes separate, as the NOP
> case is trivial. No need to complicate the trivial and common updates
> (jump_labels and ftrace). But for things like kprobes, we could do a bit
> more complex code, but it should probably be separate.

Don't mind, kprobes optimization code prepares the destination code
buffer to jump in before code patching. Thus, we just need to give the
buffer address to text_poke_bp().

Thank you,

-- 
Masami HIRAMATSU
IT Management Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com



  parent reply	other threads:[~2013-07-12  1:00 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-07-10 20:25 [RFC] [PATCH 0/2] x86: make jump labels use int3-based breakpoint instead of stop_machine() Jiri Kosina
2013-07-10 20:25 ` [RFC] [PATCH 1/2] x86: introduce int3-based instruction patching Jiri Kosina
2013-07-10 21:31   ` [RFC] [PATCH 1/2 v2] " Jiri Kosina
2013-07-10 21:36     ` H. Peter Anvin
2013-07-10 21:48       ` Borislav Petkov
2013-07-10 21:56         ` H. Peter Anvin
2013-07-10 22:14           ` Borislav Petkov
2013-07-10 22:39       ` Jiri Kosina
2013-07-11  3:29       ` Masami Hiramatsu
2013-07-11 10:09       ` Jiri Kosina
2013-07-11 10:54         ` Jiri Kosina
2013-07-11 16:31         ` H. Peter Anvin
2013-07-11 16:46           ` Steven Rostedt
2013-07-11 19:21             ` Jiri Kosina
2013-07-12  1:00             ` Masami Hiramatsu [this message]
2013-07-11 14:35       ` Steven Rostedt
2013-07-11 14:47         ` Jason Baron
2013-07-10 21:46     ` Joe Perches
2013-07-11 10:23     ` Masami Hiramatsu
2013-07-11 10:51       ` Jiri Kosina
2013-07-12  0:50         ` Masami Hiramatsu
2013-07-11 16:10       ` H. Peter Anvin
2013-07-11 19:29         ` Jiri Kosina
2013-07-11 20:49           ` H. Peter Anvin
2013-07-11 20:51           ` H. Peter Anvin
2013-07-11 15:57     ` Steven Rostedt
2013-07-11 19:43       ` Jiri Kosina
2013-07-11 19:52         ` Steven Rostedt
2013-07-10 20:25 ` [RFC] [PATCH 2/2] x86: make jump_label use int3-based patching Jiri Kosina
2013-07-10 22:26 ` [RFC] [PATCH 0/2] x86: make jump labels use int3-based breakpoint instead of stop_machine() Jason Baron
2013-07-11  0:04   ` Jiri Kosina
2013-07-11 16:42     ` Steven Rostedt
2013-07-11 19:23       ` Jiri Kosina
2013-07-11 19:54         ` Steven Rostedt
2013-07-11  2:21 ` Masami Hiramatsu
2013-07-11 20:26 ` [PATCH 2/2 v3] x86: make jump_label use int3-based patching Jiri Kosina
2013-07-12  2:12   ` Steven Rostedt
2013-07-12  5:44   ` Masami Hiramatsu
2013-07-11 20:26 ` [PATCH 1/2 v3] x86: introduce int3-based instruction patching Jiri Kosina
2013-07-11 20:53   ` H. Peter Anvin
2013-07-11 21:04     ` Borislav Petkov
2013-07-11 21:36       ` H. Peter Anvin
2013-07-12  7:57         ` Borislav Petkov
2013-07-17  3:59           ` H. Peter Anvin
2013-07-11 22:31     ` Jiri Kosina
2013-07-12  2:09       ` Steven Rostedt
2013-07-11 23:01   ` Joe Perches
2013-07-12  2:07   ` Steven Rostedt
2013-07-12  2:40   ` Masami Hiramatsu
2013-07-12  9:21 ` [PATCH 1/2 v4] " Jiri Kosina
2013-07-17  1:18   ` [tip:x86/jumplabel] x86: Introduce int3 (breakpoint) -based " tip-bot for Jiri Kosina
2013-07-12  9:22 ` [PATCH 2/2 v4] x86: make jump_label use int3-based patching Jiri Kosina
2013-07-17  1:18   ` [tip:x86/jumplabel] x86: Make " tip-bot for Jiri Kosina

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