ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 32 insertions, 0 deletions

diff --git a/tools/perf/ui/keysyms.h b/tools/perf/ui/keysyms.h
new file mode 100644
index 000000000..969060edc
--- /dev/null
+++ b/tools/perf/ui/keysyms.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _PERF_KEYSYMS_H_
+#define _PERF_KEYSYMS_H_ 1
+
+#include "libslang.h"
+
+#define K_DOWN	SL_KEY_DOWN
+#define K_END	SL_KEY_END
+#define K_ENTER	'\r'
+#define K_ESC	033
+#define K_F1	SL_KEY_F(1)
+#define K_HOME	SL_KEY_HOME
+#define K_LEFT	SL_KEY_LEFT
+#define K_PGDN	SL_KEY_NPAGE
+#define K_PGUP	SL_KEY_PPAGE
+#define K_RIGHT	SL_KEY_RIGHT
+#define K_TAB	'\t'
+#define K_UNTAB	SL_KEY_UNTAB
+#define K_UP	SL_KEY_UP
+#define K_BKSPC 0x7f
+#define K_DEL	SL_KEY_DELETE
+
+/* Not really keys */
+#define K_TIMER	 -1
+#define K_ERROR	 -2
+#define K_RESIZE -3
+#define K_SWITCH_INPUT_DATA -4
+#define K_RELOAD -5
+
+const char *key_name(int key, char *bf, size_t size);
+
+#endif /* _PERF_KEYSYMS_H_ */