Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 2d5e067e authored by Masami Hiramatsu's avatar Masami Hiramatsu Committed by Frederic Weisbecker
Browse files

tracing/kprobes: Fix trace_probe registration order 



Fix trace_probe registration order. ftrace_event_call and ftrace_event
must be registered before kprobe/kretprobe, because tracing/profiling
handlers dereference the event-id.

Signed-off-by: default avatarMasami Hiramatsu <mhiramat@redhat.com>
Acked-by: default avatarSteven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <20090914204856.18779.52961.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
parent f52487e9

kernel/trace/trace_kprobe.c

+19 −23
Original line number Diff line number Diff line
@@ -347,20 +347,15 @@ static struct trace_probe *find_probe_event(const char *event) 
	return NULL;

}



static void __unregister_trace_probe(struct trace_probe *tp)

/* Unregister a trace_probe and probe_event: call with locking probe_lock */

static void unregister_trace_probe(struct trace_probe *tp)

{

	if (probe_is_return(tp))

		unregister_kretprobe(&tp->rp);

	else

		unregister_kprobe(&tp->rp.kp);

}



/* Unregister a trace_probe and probe_event: call with locking probe_lock */

static void unregister_trace_probe(struct trace_probe *tp)

{

	unregister_probe_event(tp);

	__unregister_trace_probe(tp);

	list_del(&tp->list);

	unregister_probe_event(tp);

}



/* Register a trace_probe and probe_event */
@@ -371,6 +366,19 @@ static int register_trace_probe(struct trace_probe *tp) 


	mutex_lock(&probe_lock);



	/* register as an event */

	old_tp = find_probe_event(tp->call.name);

	if (old_tp) {

		/* delete old event */

		unregister_trace_probe(old_tp);

		free_trace_probe(old_tp);

	}

	ret = register_probe_event(tp);

	if (ret) {

		pr_warning("Faild to register probe event(%d)\n", ret);

		goto end;

	}



	if (probe_is_return(tp))

		ret = register_kretprobe(&tp->rp);

	else
@@ -384,20 +392,8 @@ static int register_trace_probe(struct trace_probe *tp) 
				   tp->rp.kp.addr);

			ret = -EINVAL;

		}

		goto end;

	}

	/* register as an event */

	old_tp = find_probe_event(tp->call.name);

	if (old_tp) {

		/* delete old event */

		unregister_trace_probe(old_tp);

		free_trace_probe(old_tp);

	}

	ret = register_probe_event(tp);

	if (ret) {

		pr_warning("Faild to register probe event(%d)\n", ret);

		__unregister_trace_probe(tp);

	}

		unregister_probe_event(tp);

	} else

		list_add_tail(&tp->list, &probe_list);

end:

	mutex_unlock(&probe_lock);