git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From 50f9ad607ea891a9308e67b81f774c71736d1098 Mon Sep 17 00:00:00 2001
   2 From: Kaitao Cheng <pilgrimtao@gmail.com>
   3 Date: Tue, 31 Dec 2019 05:35:30 -0800
   4 Subject: kernel/trace: Fix do not unregister tracepoints when register sched_migrate_task fail
   5
   6 From: Kaitao Cheng <pilgrimtao@gmail.com>
   7
   8 commit 50f9ad607ea891a9308e67b81f774c71736d1098 upstream.
   9
  10 In the function, if register_trace_sched_migrate_task() returns error,
  11 sched_switch/sched_wakeup_new/sched_wakeup won't unregister. That is
  12 why fail_deprobe_sched_switch was added.
  13
  14 Link: http://lkml.kernel.org/r/20191231133530.2794-1-pilgrimtao@gmail.com
  15
  16 Cc: stable@vger.kernel.org
  17 Fixes: 478142c39c8c2 ("tracing: do not grab lock in wakeup latency function tracing")
  18 Signed-off-by: Kaitao Cheng <pilgrimtao@gmail.com>
  19 Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
  20 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  21
  22 ---
  23  kernel/trace/trace_sched_wakeup.c |    4 +++-
  24  1 file changed, 3 insertions(+), 1 deletion(-)
  25
  26 --- a/kernel/trace/trace_sched_wakeup.c
  27 +++ b/kernel/trace/trace_sched_wakeup.c
  28 @@ -630,7 +630,7 @@ static void start_wakeup_tracer(struct t
  29         if (ret) {
  30                 pr_info("wakeup trace: Couldn't activate tracepoint"
  31                         " probe to kernel_sched_migrate_task\n");
  32 -               return;
  33 +               goto fail_deprobe_sched_switch;
  34         }
  35
  36         wakeup_reset(tr);
  37 @@ -648,6 +648,8 @@ static void start_wakeup_tracer(struct t
  38                 printk(KERN_ERR "failed to start wakeup tracer\n");
  39
  40         return;
  41 +fail_deprobe_sched_switch:
  42 +       unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL);
  43  fail_deprobe_wake_new:
  44         unregister_trace_sched_wakeup_new(probe_wakeup, NULL);
  45  fail_deprobe: