tracing/perf: Fix double put of trace event when init fails

jira LE-1907
Rebuild_History Non-Buildable kernel-3.10.0-1160.118.1.el7
commit-author Steven Rostedt (Google) <rostedt@goodmis.org>
commit 7249921
Empty-Commit: Cherry-Pick Conflicts during history rebuild.
Will be included in final tarball splat. Ref for failed cherry-pick at:
ciq/ciq_backports/kernel-3.10.0-1160.118.1.el7/7249921d.failed

If in perf_trace_event_init(), the perf_trace_event_open() fails, then it
will call perf_trace_event_unreg() which will not only unregister the perf
trace event, but will also call the put() function of the tp_event.

The problem here is that the trace_event_try_get_ref() is called by the
caller of perf_trace_event_init() and if perf_trace_event_init() returns a
failure, it will then call trace_event_put(). But since the
perf_trace_event_unreg() already called the trace_event_put() function, it
triggers a WARN_ON().

 WARNING: CPU: 1 PID: 30309 at kernel/trace/trace_dynevent.c:46 trace_event_dyn_put_ref+0x15/0x20

If perf_trace_event_reg() does not call the trace_event_try_get_ref() then
the perf_trace_event_unreg() should not be calling trace_event_put(). This
breaks symmetry and causes bugs like these.

Pull out the trace_event_put() from perf_trace_event_unreg() and call it
in the locations that perf_trace_event_unreg() is called. This not only
fixes this bug, but also brings back the proper symmetry of the reg/unreg
vs get/put logic.

Link: https://lore.kernel.org/all/cover.1660347763.git.kjlx@templeofstupid.com/
Link: https://lkml.kernel.org/r/20220816192817.43d5e17f@gandalf.local.home

	Cc: stable@vger.kernel.org
Fixes: 1d18538 ("tracing: Have dynamic events have a ref counter")
	Reported-by: Krister Johansen <kjlx@templeofstupid.com>
	Reviewed-by: Krister Johansen <kjlx@templeofstupid.com>
	Tested-by: Krister Johansen <kjlx@templeofstupid.com>
	Acked-by: Jiri Olsa <jolsa@kernel.org>
	Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
(cherry picked from commit 7249921)
	Signed-off-by: Jonathan Maple <jmaple@ciq.com>

# Conflicts:
#	kernel/trace/trace_event_perf.c

Author: PlaidCat

ciq/ciq_backports/kernel-3.10.0-1160.118.1.el7/7249921d.failed

@@ -0,0 +1,63 @@
+tracing/perf: Fix double put of trace event when init fails
+
+jira LE-1907
+Rebuild_History Non-Buildable kernel-3.10.0-1160.118.1.el7
+commit-author Steven Rostedt (Google) <rostedt@goodmis.org>
+commit 7249921d94ff64f67b733eca0b68853a62032b3d
+Empty-Commit: Cherry-Pick Conflicts during history rebuild.
+Will be included in final tarball splat. Ref for failed cherry-pick at:
+ciq/ciq_backports/kernel-3.10.0-1160.118.1.el7/7249921d.failed
+
+If in perf_trace_event_init(), the perf_trace_event_open() fails, then it
+will call perf_trace_event_unreg() which will not only unregister the perf
+trace event, but will also call the put() function of the tp_event.
+
+The problem here is that the trace_event_try_get_ref() is called by the
+caller of perf_trace_event_init() and if perf_trace_event_init() returns a
+failure, it will then call trace_event_put(). But since the
+perf_trace_event_unreg() already called the trace_event_put() function, it
+triggers a WARN_ON().
+
+ WARNING: CPU: 1 PID: 30309 at kernel/trace/trace_dynevent.c:46 trace_event_dyn_put_ref+0x15/0x20
+
+If perf_trace_event_reg() does not call the trace_event_try_get_ref() then
+the perf_trace_event_unreg() should not be calling trace_event_put(). This
+breaks symmetry and causes bugs like these.
+
+Pull out the trace_event_put() from perf_trace_event_unreg() and call it
+in the locations that perf_trace_event_unreg() is called. This not only
+fixes this bug, but also brings back the proper symmetry of the reg/unreg
+vs get/put logic.
+
+Link: https://lore.kernel.org/all/cover.1660347763.git.kjlx@templeofstupid.com/
+Link: https://lkml.kernel.org/r/20220816192817.43d5e17f@gandalf.local.home
+
+	Cc: stable@vger.kernel.org
+Fixes: 1d18538e6a092 ("tracing: Have dynamic events have a ref counter")
+	Reported-by: Krister Johansen <kjlx@templeofstupid.com>
+	Reviewed-by: Krister Johansen <kjlx@templeofstupid.com>
+	Tested-by: Krister Johansen <kjlx@templeofstupid.com>
+	Acked-by: Jiri Olsa <jolsa@kernel.org>
+	Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
+(cherry picked from commit 7249921d94ff64f67b733eca0b68853a62032b3d)
+	Signed-off-by: Jonathan Maple <jmaple@ciq.com>
+
+# Conflicts:
+#	kernel/trace/trace_event_perf.c
+diff --cc kernel/trace/trace_event_perf.c
+index df312b12b40f,61e3a2620fa3..000000000000
+--- a/kernel/trace/trace_event_perf.c
++++ b/kernel/trace/trace_event_perf.c
+@@@ -146,8 -176,6 +146,11 @@@ static void perf_trace_event_unreg(stru
+  			perf_trace_buf[i] = NULL;
+  		}
+  	}
+++<<<<<<< HEAD
+ +out:
+ +	module_put(tp_event->mod);
+++=======
+++>>>>>>> 7249921d94ff (tracing/perf: Fix double put of trace event when init fails)
+  }
+  
+  static int perf_trace_event_open(struct perf_event *p_event)
+* Unmerged path kernel/trace/trace_event_perf.c