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, 37 insertions, 0 deletions

diff --git a/drivers/thermal/mediatek/Kconfig b/drivers/thermal/mediatek/Kconfig
new file mode 100644
index 000000000..d82c86d9b
--- /dev/null
+++ b/drivers/thermal/mediatek/Kconfig
@@ -0,0 +1,37 @@
+config MTK_THERMAL
+	tristate "MediaTek thermal drivers"
+	depends on THERMAL_OF
+	help
+	  This is the option for MediaTek thermal software solutions.
+	  Please enable corresponding options to get temperature
+	  information from thermal sensors or turn on throttle
+	  mechaisms for thermal mitigation.
+
+if MTK_THERMAL
+
+config MTK_SOC_THERMAL
+	tristate "AUXADC temperature sensor driver for MediaTek SoCs"
+	depends on HAS_IOMEM
+	help
+	  Enable this option if you want to get SoC temperature
+	  information for MediaTek platforms.
+	  This driver configures thermal controllers to collect
+	  temperature via AUXADC interface.
+
+config MTK_LVTS_THERMAL
+        tristate "LVTS Thermal Driver for MediaTek SoCs"
+        depends on HAS_IOMEM
+        help
+          Enable this option if you want to get SoC temperature
+          information for supported MediaTek platforms.
+          This driver configures LVTS (Low Voltage Thermal Sensor)
+          thermal controllers to collect temperatures via ASIF
+          (Analog Serial Interface).
+
+config MTK_LVTS_THERMAL_DEBUGFS
+       bool "LVTS thermal debugfs"
+       depends on MTK_LVTS_THERMAL && DEBUG_FS
+       help
+         Enable this option to debug the internals of the device driver.
+
+endif