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, 23 insertions, 0 deletions

diff --git a/drivers/thermal/st/Kconfig b/drivers/thermal/st/Kconfig
new file mode 100644
index 000000000..ecbdf4ef0
--- /dev/null
+++ b/drivers/thermal/st/Kconfig
@@ -0,0 +1,23 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# STMicroelectronics thermal drivers configuration
+#
+
+config ST_THERMAL
+	tristate "Thermal sensors on STMicroelectronics STi series of SoCs"
+	help
+	  Support for thermal sensors on STMicroelectronics STi series of SoCs.
+
+config ST_THERMAL_MEMMAP
+	select ST_THERMAL
+	tristate "STi series memory mapped access based thermal sensors"
+
+config STM32_THERMAL
+	tristate "Thermal framework support on STMicroelectronics STM32 series of SoCs"
+	depends on MACH_STM32MP157
+	default y
+	help
+	  Support for thermal framework on STMicroelectronics STM32 series of
+	  SoCs. This thermal driver allows to access to general thermal framework
+	  functionalities and to access to SoC sensor functionalities. This
+	  configuration is fully dependent of MACH_STM32MP157.