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, 31 insertions, 0 deletions

diff --git a/drivers/clk/xilinx/Kconfig b/drivers/clk/xilinx/Kconfig
new file mode 100644
index 000000000..051756953
--- /dev/null
+++ b/drivers/clk/xilinx/Kconfig
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0
+
+config XILINX_VCU
+	tristate "Xilinx VCU logicoreIP Init"
+	depends on HAS_IOMEM
+	select REGMAP_MMIO
+	help
+	  Provides the driver to enable and disable the isolation between the
+	  processing system and programmable logic part by using the logicoreIP
+	  register set. This driver also configures the frequency based on the
+	  clock information from the logicoreIP register set.
+
+	  If you say yes here you get support for the logicoreIP.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called xlnx_vcu.
+
+config COMMON_CLK_XLNX_CLKWZRD
+	tristate "Xilinx Clocking Wizard"
+	depends on OF
+	depends on HAS_IOMEM
+	help
+	  Support for the Xilinx Clocking Wizard IP core clock generator.
+	  Adds support for clocking wizard and compatible.
+	  This driver supports the Xilinx clocking wizard programmable clock
+	  synthesizer. The number of output is configurable in the design.
+
+	  If unsure, say N.
+