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, 103 insertions, 0 deletions

diff --git a/drivers/i3c/master/Kconfig b/drivers/i3c/master/Kconfig
new file mode 100644
index 000000000..da96d2aaa
--- /dev/null
+++ b/drivers/i3c/master/Kconfig
@@ -0,0 +1,103 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config ADI_I3C_MASTER
+	tristate "Analog Devices I3C master driver"
+	depends on HAS_IOMEM
+	help
+	  Support for Analog Devices I3C Controller IP, an AXI-interfaced IP
+	  core that supports I3C and I2C devices, multiple speed-grades and I3C
+	  IBIs.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called adi-i3c-master.
+
+config CDNS_I3C_MASTER
+	tristate "Cadence I3C master driver"
+	depends on HAS_IOMEM
+	depends on !(ALPHA || PARISC)
+	help
+	  Enable this driver if you want to support Cadence I3C master block.
+
+config DW_I3C_MASTER
+	tristate "Synospsys DesignWare I3C master driver"
+	depends on HAS_IOMEM
+	depends on !(ALPHA || PARISC)
+	# ALPHA and PARISC needs {read,write}sl()
+	help
+	  Support for Synopsys DesignWare MIPI I3C Controller.
+
+	  For details please see
+	  https://www.synopsys.com/dw/ipdir.php?ds=mipi_i3c
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called dw-i3c-master.
+
+config AST2600_I3C_MASTER
+	tristate "ASPEED AST2600 I3C master driver"
+	depends on DW_I3C_MASTER
+	depends on ARCH_ASPEED || COMPILE_TEST
+	select MFD_SYSCON
+	help
+	  Support for ASPEED AST2600 I3C Controller.
+
+	  This hardware is an instance of the DW I3C controller; this
+	  driver adds platform- specific support for AST2600 hardware.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called ast2600-i3c-master.
+
+config SVC_I3C_MASTER
+	tristate "Silvaco I3C Dual-Role Master driver"
+	depends on HAS_IOMEM
+	depends on !(ALPHA || PARISC)
+	help
+	  Support for Silvaco I3C Dual-Role Master Controller.
+
+config MIPI_I3C_HCI
+	tristate "MIPI I3C Host Controller Interface driver (EXPERIMENTAL)"
+	depends on HAS_IOMEM
+	help
+	  Support for hardware following the MIPI Aliance's I3C Host Controller
+	  Interface specification.
+
+	  For details please see:
+	  https://www.mipi.org/specifications/i3c-hci
+
+	  This driver can also be built as a module.  If so, the module will be
+	  called mipi-i3c-hci.
+
+config MIPI_I3C_HCI_PCI
+	tristate "MIPI I3C Host Controller Interface PCI support"
+	depends on MIPI_I3C_HCI
+	depends on PCI
+	select MFD_CORE
+	help
+	  Support for MIPI I3C Host Controller Interface compatible hardware
+	  on the PCI bus.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called mipi-i3c-hci-pci.
+
+config RENESAS_I3C
+	tristate "Renesas I3C controller driver"
+	depends on HAS_IOMEM
+	depends on ARCH_RENESAS || COMPILE_TEST
+	help
+	  Support the Renesas I3C controller as found in some RZ variants.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called renesas-i3c.
+
+config AMD_AXI_I3C_MASTER
+	tristate "AMD AXI I3C Master driver"
+	depends on HAS_IOMEM
+	help
+	  Support for the AMD AXI I3C master controller, a soft IP used on
+	  AMD (Xilinx) FPGAs and adaptive SoCs with ARM or MicroBlaze
+	  processors.
+
+	  The controller currently supports Standard Data Rate (SDR) mode.
+	  Features include Dynamic Address Assignment, private transfers,
+	  and CCC transfers in both broadcast and direct modes.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called amd-i3c-master.