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, 27 insertions, 0 deletions

diff --git a/drivers/reset/amlogic/Kconfig b/drivers/reset/amlogic/Kconfig
new file mode 100644
index 000000000..3bee9fd60
--- /dev/null
+++ b/drivers/reset/amlogic/Kconfig
@@ -0,0 +1,27 @@
+config RESET_MESON_COMMON
+	tristate
+	select REGMAP
+
+config RESET_MESON
+	tristate "Meson Reset Driver"
+	depends on ARCH_MESON || COMPILE_TEST
+	default ARCH_MESON
+	select REGMAP_MMIO
+	select RESET_MESON_COMMON
+	help
+	  This enables the reset driver for Amlogic SoCs.
+
+config RESET_MESON_AUX
+	tristate "Meson Reset Auxiliary Driver"
+	depends on ARCH_MESON || COMPILE_TEST
+	select AUXILIARY_BUS
+	select RESET_MESON_COMMON
+	help
+	  This enables the reset auxiliary driver for Amlogic SoCs.
+
+config RESET_MESON_AUDIO_ARB
+	tristate "Meson Audio Memory Arbiter Reset Driver"
+	depends on ARCH_MESON || COMPILE_TEST
+	help
+	  This enables the reset driver for Audio Memory Arbiter of
+	  Amlogic's A113 based SoCs