Re: [PATCH v5 0/3] tracing: kprobes: Prohibit probing on notrace functions

[Francis Deslauriers]

Hi Masami,
I just tested the patch-set and it still prevents the crash I was witnessing.
You can add my tested-by.
Tested-by: Francis Deslauriers <francis.deslauriers@xxxxxxxxxxxx>

Thank you for pushing this forward!
Francis
Le lun. 30 juill. 2018, Ã 06 h 20, Masami Hiramatsu
<mhiramat@xxxxxxxxxx> a Ãcrit :
>
> Hi,
>
> This is the 5th version of the series to prohibit kprobe
> on notrace functions.
>
> This fixes a build error when CONFIG_FUNCTION_TRACER=y but
> DYNAMIC_FTRACE=n. Finally I decided to recover the approach
> in the 1st version, made it depends on CONFIG_KPROBES_ON_FTRACE=y.
> It is the simplest and enough to prohibiting kernel crash.
>
> So, in summary, if CONFIG_KPROBES_ON_FTRACE=y (which depends
> on CONFIG_DYNAMIC_FTRACE=y, so ftrace_location_range must be
> there) && CONFIG_KPROBE_EVENTS_ON_NOTRACE=n (default),
> kprobe events can not be defined on notrace function.
> Otherwides (means CONFIG_KPROBES_ON_FTRACE=n or
> CONFIG_KPROBE_EVENTS_ON_NOTRACE=y), we can put kprobe events
> on notrace functions.
>
> Francis, I dropped your tested-by because I got many kbuild
> errors and fixed it. If you can, could you test it again?
>
> Thank you,
>
> ---
>
> Francis Deslauriers (1):
>       selftest/ftrace: Move kprobe selftest function to separate compile unit
>
> Masami Hiramatsu (2):
>       tracing: kprobes: Prohibit probing on notrace function
>       selftests/ftrace: Fix kprobe string testcase to not probe notrace function
>
>
>  kernel/trace/Kconfig                               |   20 +++++++
>  kernel/trace/Makefile                              |    5 ++
>  kernel/trace/trace_kprobe.c                        |   59 +++++++++++++-------
>  kernel/trace/trace_kprobe_selftest.c               |   10 +++
>  kernel/trace/trace_kprobe_selftest.h               |    7 ++
>  .../ftrace/test.d/kprobe/kprobe_args_string.tc     |   30 ++++------
>  .../selftests/ftrace/test.d/kprobe/probepoint.tc   |    2 -
>  7 files changed, 94 insertions(+), 39 deletions(-)
>  create mode 100644 kernel/trace/trace_kprobe_selftest.c
>  create mode 100644 kernel/trace/trace_kprobe_selftest.h
>
> --
> Masami Hiramatsu (Linaro) <mhiramat@xxxxxxxxxx>



--
Francis Deslauriers
Software developer
EfficiOS inc.