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Re: Kprobes support for accessing args upon return

From: "Jun Koi" <junkoi2004 at gmail dot com>
To: "Jim Keniston" <jkenisto at us dot ibm dot com>
Cc: SystemTAP <systemtap at sources dot redhat dot com>
Date: Sat, 16 Dec 2006 19:13:28 +0900
Subject: Re: Kprobes support for accessing args upon return
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References: <1165444360.2874.18.camel@dyn9047018079.beaverton.ibm.com> <fdaac4d50612160207r18545781v43f57bcce8aadad6@mail.gmail.com>

BTW, is there any way to know if a kernel is compiled with or without
the "frame pointer" option? (I suppose that we dont have the .config
file at hand)

Thanks,
Jun

On 12/16/06, Jun Koi <junkoi2004@gmail.com> wrote:

Hi Jim,

On 06 Dec 2006 14:32:40 -0800, Jim Keniston <jkenisto@us.ibm.com> wrote:
> As promised, here (once again) is a pointer to the kretprobes patch
> (against 2.6.13) that adds an optional "data pouch" to a
> kretprobe_instance. This makes it easy for data such as arg values to be
> saved upon function entry and recalled upon return.  This was written by
> Kevin Stafford and smoke-tested by me.

This patch would be very useful. However, there is a doubt: You access
function args by ESP. That would not work if the kernel compiled
without "frame pointer" option.

But this patch is worthy to be merged IMO.

regards,
J

References:
- Kprobes support for accessing args upon return
  - From: Jim Keniston
- Re: Kprobes support for accessing args upon return
  - From: Jun Koi

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