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, 51 insertions, 0 deletions

diff --git a/drivers/leds/simatic/Kconfig b/drivers/leds/simatic/Kconfig
new file mode 100644
index 000000000..e616cc6d6
--- /dev/null
+++ b/drivers/leds/simatic/Kconfig
@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config LEDS_SIEMENS_SIMATIC_IPC
+	tristate "LED driver for Siemens Simatic IPCs"
+	depends on LEDS_CLASS
+	depends on SIEMENS_SIMATIC_IPC
+	default y
+	help
+	  This option enables support for the LEDs of several Industrial PCs
+	  from Siemens.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called simatic-ipc-leds.
+
+config LEDS_SIEMENS_SIMATIC_IPC_APOLLOLAKE
+	tristate "LED driver for Siemens Simatic IPCs based on Intel Apollo Lake GPIO"
+	depends on LEDS_GPIO
+	depends on PINCTRL_BROXTON
+	depends on SIEMENS_SIMATIC_IPC
+	default LEDS_SIEMENS_SIMATIC_IPC
+	help
+	  This option enables support for the LEDs of several Industrial PCs
+	  from Siemens based on Apollo Lake GPIO i.e. IPC127E.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called simatic-ipc-leds-gpio-apollolake.
+
+config LEDS_SIEMENS_SIMATIC_IPC_F7188X
+	tristate "LED driver for Siemens Simatic IPCs based on Nuvoton GPIO"
+	depends on LEDS_GPIO
+	depends on GPIO_F7188X
+	depends on SIEMENS_SIMATIC_IPC
+	default LEDS_SIEMENS_SIMATIC_IPC
+	help
+	  This option enables support for the LEDs of several Industrial PCs
+	  from Siemens based on Nuvoton GPIO i.e. IPC227G.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called simatic-ipc-leds-gpio-f7188x.
+
+config LEDS_SIEMENS_SIMATIC_IPC_ELKHARTLAKE
+	tristate "LED driver for Siemens Simatic IPCs based on Intel Elkhart Lake GPIO"
+	depends on LEDS_GPIO
+	depends on PINCTRL_ELKHARTLAKE
+	depends on SIEMENS_SIMATIC_IPC
+	default LEDS_SIEMENS_SIMATIC_IPC
+	help
+	  This option enables support for the LEDs of several Industrial PCs
+	  from Siemens based on Elkhart Lake GPIO i.e. BX-21A.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called simatic-ipc-leds-gpio-elkhartlake.