diff options
| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2018-07-25 22:28:56 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-08-03 07:55:12 +0200 |
| commit | b985a7303de1d25e6040f7c7693072acfc6139ae (patch) | |
| tree | e0dbb5b4fbb9e9ea7fbf96ff531c55a0cffaae79 /kernel | |
| parent | 987e425ad386543e8d8c3fc9a2530424fc3eb575 (diff) | |
tracing: Quiet gcc warning about maybe unused link variable
commit 2519c1bbe38d7acacc9aacba303ca6f97482ed53 upstream.
Commit 57ea2a34adf4 ("tracing/kprobes: Fix trace_probe flags on
enable_trace_kprobe() failure") added an if statement that depends on another
if statement that gcc doesn't see will initialize the "link" variable and
gives the warning:
"warning: 'link' may be used uninitialized in this function"
It is really a false positive, but to quiet the warning, and also to make
sure that it never actually is used uninitialized, initialize the "link"
variable to NULL and add an if (!WARN_ON_ONCE(!link)) where the compiler
thinks it could be used uninitialized.
Cc: stable@vger.kernel.org
Fixes: 57ea2a34adf4 ("tracing/kprobes: Fix trace_probe flags on enable_trace_kprobe() failure")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace_kprobe.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index f76c0e1433c0..3b4cd44ad323 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -359,7 +359,7 @@ static struct trace_kprobe *find_trace_kprobe(const char *event, static int enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) { - struct event_file_link *link; + struct event_file_link *link = NULL; int ret = 0; if (file) { @@ -385,7 +385,9 @@ enable_trace_kprobe(struct trace_kprobe *tk, struct trace_event_file *file) if (ret) { if (file) { - list_del_rcu(&link->list); + /* Notice the if is true on not WARN() */ + if (!WARN_ON_ONCE(!link)) + list_del_rcu(&link->list); kfree(link); tk->tp.flags &= ~TP_FLAG_TRACE; } else { |