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, 127 insertions, 0 deletions

diff --git a/drivers/iio/frequency/Kconfig b/drivers/iio/frequency/Kconfig
new file mode 100644
index 000000000..90c6304c4
--- /dev/null
+++ b/drivers/iio/frequency/Kconfig
@@ -0,0 +1,127 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Frequency
+#	Direct Digital Synthesis drivers (DDS)
+#	Clock Distribution device drivers
+#	Phase-Locked Loop (PLL) frequency synthesizers
+#
+# When adding new entries keep the list in alphabetical order
+
+menu "Frequency Synthesizers DDS/PLL"
+
+menu "Clock Generator/Distribution"
+
+config AD9523
+	tristate "Analog Devices AD9523 Low Jitter Clock Generator"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices AD9523 Low Jitter
+	  Clock Generator. The driver provides direct access via sysfs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called ad9523.
+
+endmenu
+
+#
+# Phase-Locked Loop (PLL) frequency synthesizers
+#
+
+menu "Phase-Locked Loop (PLL) frequency synthesizers"
+
+config ADF41513
+	tristate "Analog Devices ADF41513 PLL Frequency Synthesizer"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices ADF41513
+	  26.5 GHz Integer-N/Fractional-N PLL Frequency Synthesizer.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adf41513.
+
+config ADF4350
+	tristate "Analog Devices ADF4350/ADF4351 Wideband Synthesizers"
+	depends on SPI
+	help
+	  Say yes here to build support for Analog Devices  ADF4350/ADF4351
+	  Wideband Synthesizers. The driver provides direct access via sysfs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adf4350.
+
+config ADF4371
+	tristate "Analog Devices ADF4371/ADF4372 Wideband Synthesizers"
+	depends on SPI
+	select REGMAP_SPI
+	help
+	  Say yes here to build support for Analog Devices ADF4371 and ADF4372
+	  Wideband Synthesizers. The driver provides direct access via sysfs.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adf4371.
+
+config ADF4377
+	tristate "Analog Devices ADF4377 Microwave Wideband Synthesizer"
+	depends on SPI && COMMON_CLK
+	select REGMAP_SPI
+	help
+	  Say yes here to build support for Analog Devices ADF4377 Microwave
+	  Wideband Synthesizer.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adf4377.
+
+config ADMFM2000
+	tristate "Analog Devices ADMFM2000 Dual Microwave Down Converter"
+	depends on GPIOLIB
+	help
+	  Say yes here to build support for Analog Devices ADMFM2000 Dual
+	  Microwave Down Converter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called admfm2000.
+
+config ADMV1013
+	tristate "Analog Devices ADMV1013 Microwave Upconverter"
+	depends on SPI && COMMON_CLK
+	help
+	  Say yes here to build support for Analog Devices ADMV1013
+	  24 GHz to 44 GHz, Wideband, Microwave Upconverter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called admv1013.
+
+config ADMV1014
+	tristate "Analog Devices ADMV1014 Microwave Downconverter"
+	depends on SPI && COMMON_CLK && 64BIT
+	help
+	  Say yes here to build support for Analog Devices ADMV1014
+	  24 GHz to 44 GHz, Wideband, Microwave Downconverter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called admv1014.
+
+config ADMV4420
+	tristate "Analog Devices ADMV4420 K Band Downconverter"
+	depends on SPI
+	select REGMAP_SPI
+	help
+	  Say yes here to build support for Analog Devices K Band
+	  Downconverter with integrated Fractional-N PLL and VCO.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called admv4420.
+
+config ADRF6780
+	tristate "Analog Devices ADRF6780 Microwave Upconverter"
+	depends on SPI
+	depends on COMMON_CLK
+	help
+	  Say yes here to build support for Analog Devices ADRF6780
+	  5.9 GHz to 23.6 GHz, Wideband, Microwave Upconverter.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called adrf6780.
+
+endmenu
+endmenu