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, 32 insertions, 0 deletions

diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig
new file mode 100644
index 000000000..50d2051f7
--- /dev/null
+++ b/drivers/tee/optee/Kconfig
@@ -0,0 +1,32 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# OP-TEE Trusted Execution Environment Configuration
+config OPTEE
+	tristate "OP-TEE"
+	depends on HAVE_ARM_SMCCC
+	depends on MMU
+	depends on RPMB || !RPMB
+	help
+	  This implements the OP-TEE Trusted Execution Environment (TEE)
+	  driver.
+
+config OPTEE_INSECURE_LOAD_IMAGE
+	bool "Load OP-TEE image as firmware"
+	default n
+	depends on OPTEE && ARM64
+	help
+	  This loads the BL32 image for OP-TEE as firmware when the driver is
+	  probed. This returns -EPROBE_DEFER until the firmware is loadable from
+	  the filesystem which is determined by checking the system_state until
+	  it is in SYSTEM_RUNNING. This also requires enabling the corresponding
+	  option in Trusted Firmware for Arm. The documentation there explains
+	  the security threat associated with enabling this as well as
+	  mitigations at the firmware and platform level.
+	  https://trustedfirmware-a.readthedocs.io/en/latest/threat_model/threat_model.html
+
+	  Additional documentation on kernel security risks are at
+	  Documentation/tee/op-tee.rst.
+
+config OPTEE_STATIC_PROTMEM_POOL
+	bool
+	depends on HAS_IOMEM && TEE_DMABUF_HEAPS
+	default y