From: Masami Hiramatsu mhiramat@kernel.org

Enable the notrace function check on the architecture which doesn't support kprobes on ftrace but support dynamic ftrace. This notrace function check is not only for the kprobes on ftrace but also sw-breakpoint based kprobes. Thus there is no reason to limit this check for the arch which supports kprobes on ftrace.

This also changes the dependency of Kconfig. Because kprobe event uses the function tracer's address list for identifying notrace function, if the CONFIG_DYNAMIC_FTRACE=n, it can not check whether the target function is notrace or not.

Link: https://lkml.kernel.org/r/20210105065730.2634785-1-naveen.n.rao@linux.vnet.i... Link: https://lkml.kernel.org/r/161007957862.114704.4512260007555399463.stgit@devn...

Cc: stable@vger.kernel.org Fixes: 45408c4f92506 ("tracing: kprobes: Prohibit probing on notrace function") Acked-by: Naveen N. Rao naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Masami Hiramatsu mhiramat@kernel.org Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org --- kernel/trace/Kconfig | 2 +- kernel/trace/trace_kprobe.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index d5a19413d4f8..c1a62ae7e812 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -538,7 +538,7 @@ config KPROBE_EVENTS config KPROBE_EVENTS_ON_NOTRACE bool "Do NOT protect notrace function from kprobe events" depends on KPROBE_EVENTS - depends on KPROBES_ON_FTRACE + depends on DYNAMIC_FTRACE default n help This is only for the developers who want to debug ftrace itself diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 9c31f42245e9..e6fba1798771 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -434,7 +434,7 @@ static int disable_trace_kprobe(struct trace_event_call *call, return 0; }

-#if defined(CONFIG_KPROBES_ON_FTRACE) && \ +#if defined(CONFIG_DYNAMIC_FTRACE) && \ !defined(CONFIG_KPROBE_EVENTS_ON_NOTRACE) static bool __within_notrace_func(unsigned long addr) {