From mboxrd@z Thu Jan 1 00:00:00 1970 From: rostedt@goodmis.org (Steven Rostedt) Date: Tue, 19 Jun 2018 09:17:35 -0400 Subject: Dynamic ftrace self test broken on ARM In-Reply-To: References: <65fb14b356bc0a414f1fe5cf5c6eb395@agner.ch> <20180618175437.3e6c85a1@gandalf.local.home> Message-ID: <20180619091735.7aec75d0@gandalf.local.home> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, 19 Jun 2018 10:16:19 +0200 Stefan Agner wrote: > > I'm guessing that it boots fine with CONFIG_FTRACE_STARTUP_TEST=n? Can > > you try disable the tracers to see if it's the function graph or > > function tracer that is causing the issue? That is, turn off > > CONFIG_FUNCTION_GRAPH_TRACER and test it again, and if that crashes, > > turn off CONFIG_FUNCTION_TRACER to make sure the crash goes away there > > too. > > Without CONFIG_FTRACE_STARTUP_TEST the kernel boots fine. > > CONFIG_FUNCTION_TRACER=y > # CONFIG_FUNCTION_GRAPH_TRACER is not set > # CONFIG_SCHED_TRACER is not set > CONFIG_FTRACE_STARTUP_TEST=y OK, so it's not a graph tracer issue, but a function tracer issue. > > Crashes with the same stack trace. > > # CONFIG_FUNCTION_TRACER is not set > CONFIG_SCHED_TRACER=y > CONFIG_FTRACE_STARTUP_TEST=y > > Runs tracer tests and boots fine. Thanks. Did this ever work? And if so, perhaps you have time to perform a bisect. If you have a ktest setup, you can have it run the bisect for you (over night). -- Steve