Merge tag 'trace-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing update from Steven Rostedt:
 "This batch of changes is mostly clean ups and small bug fixes.  The
  only real feature that was added this release is from Namhyung Kim,
  who introduced "set_graph_notrace" filter that lets you run the
  function graph tracer and not trace particular functions and their
  call chain.

  Tom Zanussi added some updates to the ftrace multibuffer tracing that
  made it more consistent with the top level tracing.

  One of the fixes for perf function tracing required an API change in
  RCU; the addition of "rcu_is_watching()".  As Paul McKenney is pushing
  that change in this release too, he gave me a branch that included all
  the changes to get that working, and I pulled that into my tree in
  order to complete the perf function tracing fix"

* tag 'trace-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Add rcu annotation for syscall trace descriptors
  tracing: Do not use signed enums with unsigned long long in fgragh output
  tracing: Remove unused function ftrace_off_permanent()
  tracing: Do not assign filp->private_data to freed memory
  tracing: Add helper function tracing_is_disabled()
  tracing: Open tracer when ftrace_dump_on_oops is used
  tracing: Add support for SOFT_DISABLE to syscall events
  tracing: Make register/unregister_ftrace_command __init
  tracing: Update event filters for multibuffer
  recordmcount.pl: Add support for __fentry__
  ftrace: Have control op function callback only trace when RCU is watching
  rcu: Do not trace rcu_is_watching() functions
  ftrace/x86: skip over the breakpoint for ftrace caller
  trace/trace_stat: use rbtree postorder iteration helper instead of opencoding
  ftrace: Add set_graph_notrace filter
  ftrace: Narrow down the protected area of graph_lock
  ftrace: Introduce struct ftrace_graph_data
  ftrace: Get rid of ftrace_graph_filter_enabled
  tracing: Fix potential out-of-bounds in trace_get_user()
  tracing: Show more exact help information about snapshot

1 files changed, 13 insertions, 1 deletions

diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 42a392a9fd02..d4bdd253fea7 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -248,6 +248,15 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 	return ret;
 }
 
+static int is_ftrace_caller(unsigned long ip)
+{
+	if (ip == (unsigned long)(&ftrace_call) ||
+		ip == (unsigned long)(&ftrace_regs_call))
+		return 1;
+
+	return 0;
+}
+
 /*
  * A breakpoint was added to the code address we are about to
  * modify, and this is the handle that will just skip over it.
@@ -257,10 +266,13 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
  */
 int ftrace_int3_handler(struct pt_regs *regs)
 {
+	unsigned long ip;
+
 	if (WARN_ON_ONCE(!regs))
 		return 0;
 
-	if (!ftrace_location(regs->ip - 1))
+	ip = regs->ip - 1;
+	if (!ftrace_location(ip) && !is_ftrace_caller(ip))
 		return 0;
 
 	regs->ip += MCOUNT_INSN_SIZE - 1;