Re: [PATCH 1/2] trace/kprobes: Sanitize derived event names

[Masami Hiramatsu <mhiramat@kernel.org>]

On Fri, 23 Jun 2017 00:33:45 +0530
"Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote:

> On 2017/06/22 06:29PM, Masami Hiramatsu wrote:
> > On Thu, 22 Jun 2017 00:20:27 +0530
> > "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com> wrote:
> > 
> > > When we derive event names, convert some expected symbols (such as ':'
> > > used to specify module:name and '.' present in some symbols) into
> > > underscores so that the event name is not rejected.
> > 
> > Oops, ok, this is my mistake.
> > 
> > Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
> > 
> > This must be marked as bugfix for stable trees.
> > 
> > Could you also add a testcase for this (module name) bug?
> > 
> > MODNAME=`lsmod | head -n 2 | tail -n 1 | cut -f 1 -d " "`
> > FUNCNAME=`grep -m 1 "\\[$MODNAME\\]" /proc/kallsyms | xargs | cut -f 3 -d " "`
> > 
> > May gives you a target name :)
> 
> Sure. Here is a test.
> 
> Thanks for the review,
> Naveen
> 
> -
> [PATCH] selftests/ftrace: Add a test to probe module functions
> 
> Add a kprobes test to ensure that we are able to add a probe on a
> module function using 'p <mod>:<func>' format, without having to
> specify a probe name.
> 
> Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>

Perfect! :)

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>

Thanks!

> ---
>  .../testing/selftests/ftrace/test.d/kprobe/probe_module.tc | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
>  create mode 100644 tools/testing/selftests/ftrace/test.d/kprobe/probe_module.tc
> 
> diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/probe_module.tc b/tools/testing/selftests/ftrace/test.d/kprobe/probe_module.tc
> new file mode 100644
> index 000000000000..ea7657041ba6
> --- /dev/null
> +++ b/tools/testing/selftests/ftrace/test.d/kprobe/probe_module.tc
> @@ -0,0 +1,14 @@
> +#!/bin/sh
> +# description: Kprobe dynamic event - probing module
> +
> +[ -f kprobe_events ] || exit_unsupported # this is configurable
> +
> +echo 0 > events/enable
> +echo > kprobe_events
> +export MOD=`lsmod | head -n 2 | tail -n 1 | cut -f1 -d" "`
> +export FUNC=`grep -m 1 ".* t .*\\[$MOD\\]" /proc/kallsyms | xargs | cut -f3 -d" "`
> +[ "x" != "x$MOD" -a "y" != "y$FUNC" ] || exit_untested
> +echo p $MOD:$FUNC > kprobe_events
> +grep $MOD kprobe_events
> +echo > kprobe_events
> +clear_trace
> -- 
> 2.13.1
> 


-- 
Masami Hiramatsu <mhiramat@kernel.org>