[PATCH 4.10 31/75] tracing: Fix return value check in trace_benchmark_reg()

[Greg Kroah-Hartman]

4.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Wei Yongjun <weiyongjun1@xxxxxxxxxx>

commit 8f0994bb8cbde5452e58ce0cacdbf6cb58079d01 upstream.

In case of error, the function kthread_run() returns ERR_PTR() and never
returns NULL. The NULL test in the return value check should be replaced
with IS_ERR().

Link: http://lkml.kernel.org/r/20170112135502.28556-1-weiyj.lk@xxxxxxxxx

Fixes: 81dc9f0e ("tracing: Add tracepoint benchmark tracepoint")
Signed-off-by: Wei Yongjun <weiyongjun1@xxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 kernel/trace/trace_benchmark.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/trace/trace_benchmark.c
+++ b/kernel/trace/trace_benchmark.c
@@ -175,9 +175,9 @@ int trace_benchmark_reg(void)
 
 	bm_event_thread = kthread_run(benchmark_event_kthread,
 				      NULL, "event_benchmark");
-	if (!bm_event_thread) {
+	if (IS_ERR(bm_event_thread)) {
 		pr_warning("trace benchmark failed to create kernel thread\n");
-		return -ENOMEM;
+		return PTR_ERR(bm_event_thread);
 	}
 
 	return 0;