lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 1 Nov 2017 12:44:33 -0400 From: Steven Rostedt <rostedt@...dmis.org> To: Julien Thierry <julien.thierry@....com> Cc: linux-arm-kernel@...ts.infradead.org, takahiro.akashi@...aro.org, Will Deacon <will.deacon@....com>, Mark Rutland <mark.rutland@....com>, Peter Zijlstra <peterz@...radead.org>, Ingo Molnar <mingo@...hat.com>, linux-kernel@...r.kernel.org Subject: Re: [PATCH 2/2] perf: Fix ftrace builtin when kernel doesn't have function_graph On Wed, 1 Nov 2017 14:33:44 +0000 Julien Thierry <julien.thierry@....com> wrote: > When linux is built without support for function graph tracer, the ftrace > builtin of perf will fail when trying to reset max_graph_depth because the > file does not exist. This prevents the use of function tracer from perf. > > Do not attempt to write this file when the tracer in use is not > function_graph. > > Signed-off-by: Julien Thierry <julien.thierry@....com> > Cc: Will Deacon <will.deacon@....com> > Cc: Mark Rutland <mark.rutland@....com> > Cc: Peter Zijlstra <peterz@...radead.org> > Cc: Ingo Molnar <mingo@...hat.com> > Cc: linux-kernel@...r.kernel.org > --- > tools/perf/builtin-ftrace.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c > index 25a42ac..48120f2 100644 > --- a/tools/perf/builtin-ftrace.c > +++ b/tools/perf/builtin-ftrace.c > @@ -130,7 +130,8 @@ static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused) > if (reset_tracing_cpu() < 0) > return -1; > > - if (write_tracing_file("max_graph_depth", "0") < 0) > + if (!strcmp(ftrace->tracer, "function_graph") && > + write_tracing_file("max_graph_depth", "0") < 0) Hmm, instead of doing this, could we just do a stat on the file first. As with trace-cmd, I like to reset files like this even when not enabling function_graph tracer. -- Steve > return -1; > > reset_tracing_filters(); > -- > 1.9.1
Powered by blists - more mailing lists