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

["Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>]

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>
---
 .../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