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, 41 insertions, 0 deletions

diff --git a/drivers/thermal/broadcom/Kconfig b/drivers/thermal/broadcom/Kconfig
new file mode 100644
index 000000000..061f1db6e
--- /dev/null
+++ b/drivers/thermal/broadcom/Kconfig
@@ -0,0 +1,41 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config BCM2711_THERMAL
+	tristate "Broadcom AVS RO thermal sensor driver"
+	depends on ARCH_BCM2835 || COMPILE_TEST
+	depends on THERMAL_OF && MFD_SYSCON
+	help
+	  Support for thermal sensors on Broadcom BCM2711 SoCs.
+
+config BCM2835_THERMAL
+	tristate "Thermal sensors on bcm2835 SoC"
+	depends on ARCH_BCM2835 || COMPILE_TEST
+	depends on HAS_IOMEM
+	depends on THERMAL_OF
+	help
+	  Support for thermal sensors on Broadcom bcm2835 SoCs.
+
+config BRCMSTB_THERMAL
+	tristate "Broadcom STB AVS TMON thermal driver"
+	depends on ARCH_BRCMSTB || COMPILE_TEST
+	help
+	  Enable this driver if you have a Broadcom STB SoC and would like
+	  thermal framework support.
+
+config BCM_NS_THERMAL
+	tristate "Northstar thermal driver"
+	depends on ARCH_BCM_IPROC || COMPILE_TEST
+	default y if ARCH_BCM_IPROC
+	help
+	  Support for the Northstar and Northstar Plus family of SoCs (e.g.
+	  BCM4708, BCM4709, BCM5301x, BCM95852X, etc). It contains DMU (Device
+	  Management Unit) block with a thermal sensor that allows checking CPU
+	  temperature.
+
+config BCM_SR_THERMAL
+	tristate "Stingray thermal driver"
+	depends on ARCH_BCM_IPROC || COMPILE_TEST
+	default ARCH_BCM_IPROC
+	help
+	  Support for the Stingray family of SoCs. Its different blocks like
+	  iHost, CRMU and NITRO has thermal sensor that allows checking its
+	  temperature.