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

[Masami Hiramatsu]

On Mon, 30 Jul 2018 12:06:17 -0400
Francis Deslauriers <francis.deslauriers@xxxxxxxxxxxx> wrote:

> 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>

Thanks Francis!


> 
> 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.


-- 
Masami Hiramatsu <mhiramat@xxxxxxxxxx>