releases/3.18.50/ring-buffer-fix-return-value-check-in-test_ringbuffer.patch

   1 From 62277de758b155dc04b78f195a1cb5208c37b2df Mon Sep 17 00:00:00 2001
   2 From: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
   3 Date: Fri, 17 Jun 2016 17:33:59 +0000
   4 Subject: ring-buffer: Fix return value check in test_ringbuffer()
   5
   6 From: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
   7
   8 commit 62277de758b155dc04b78f195a1cb5208c37b2df upstream.
   9
  10 In case of error, the function kthread_run() returns ERR_PTR()
  11 and never returns NULL. The NULL test in the return value check
  12 should be replaced with IS_ERR().
  13
  14 Link: http://lkml.kernel.org/r/1466184839-14927-1-git-send-email-weiyj_lk@163.com
  15
  16 Fixes: 6c43e554a ("ring-buffer: Add ring buffer startup selftest")
  17 Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
  18 Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
  19 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  20
  21 ---
  22  kernel/trace/ring_buffer.c |    8 ++++----
  23  1 file changed, 4 insertions(+), 4 deletions(-)
  24
  25 --- a/kernel/trace/ring_buffer.c
  26 +++ b/kernel/trace/ring_buffer.c
  27 @@ -4883,9 +4883,9 @@ static __init int test_ringbuffer(void)
  28                 rb_data[cpu].cnt = cpu;
  29                 rb_threads[cpu] = kthread_create(rb_test, &rb_data[cpu],
  30                                                  "rbtester/%d", cpu);
  31 -               if (WARN_ON(!rb_threads[cpu])) {
  32 +               if (WARN_ON(IS_ERR(rb_threads[cpu]))) {
  33                         pr_cont("FAILED\n");
  34 -                       ret = -1;
  35 +                       ret = PTR_ERR(rb_threads[cpu]);
  36                         goto out_free;
  37                 }
  38
  39 @@ -4895,9 +4895,9 @@ static __init int test_ringbuffer(void)
  40
  41         /* Now create the rb hammer! */
  42         rb_hammer = kthread_run(rb_hammer_test, NULL, "rbhammer");
  43 -       if (WARN_ON(!rb_hammer)) {
  44 +       if (WARN_ON(IS_ERR(rb_hammer))) {
  45                 pr_cont("FAILED\n");
  46 -               ret = -1;
  47 +               ret = PTR_ERR(rb_hammer);
  48                 goto out_free;
  49         }
  50