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, 77 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/chrome/google,cros-ec-typec.yaml b/Documentation/devicetree/bindings/chrome/google,cros-ec-typec.yaml
new file mode 100644
index 000000000..fd1a45987
--- /dev/null
+++ b/Documentation/devicetree/bindings/chrome/google,cros-ec-typec.yaml
@@ -0,0 +1,77 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/chrome/google,cros-ec-typec.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Google Chrome OS EC(Embedded Controller) Type C port driver.
+
+maintainers:
+  - Benson Leung <bleung@chromium.org>
+  - Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
+  - Andrei Kuchynski <akuchynski@chromium.org>
+  - Łukasz Bartosik <ukaszb@chromium.org>
+  - Jameson Thies <jthies@google.com>
+
+description:
+  Chrome OS devices have an Embedded Controller(EC) which has access to
+  Type C port state. This node is intended to allow the host to read and
+  control the Type C ports. This binding is compatible with both the
+  cros-ec-typec and cros-ec-ucsi drivers. The cros-ec-typec driver
+  supports the host command interface used by the Chrome OS EC with a
+  built-in Type-C port manager and external Type-C Port Controller
+  (TCPC). The cros-ec-ucsi driver supports the USB Type-C Connector
+  System Software (UCSI) interface used by the Chrome OS EC when the
+  platform has a separate power delivery controller (PDC). The node for
+  this device should be under a cros-ec node like google,cros-ec-spi.
+
+properties:
+  compatible:
+    enum:
+      - google,cros-ec-typec
+      - google,cros-ec-ucsi
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+patternProperties:
+  '^connector@[0-9a-f]+$':
+    $ref: /schemas/connector/usb-connector.yaml#
+    required:
+      - reg
+
+required:
+  - compatible
+
+additionalProperties: false
+
+examples:
+  - |+
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      cros_ec: ec@0 {
+        compatible = "google,cros-ec-spi";
+        reg = <0>;
+        interrupts = <35 0>;
+
+        typec {
+          compatible = "google,cros-ec-typec";
+
+          #address-cells = <1>;
+          #size-cells = <0>;
+
+          connector@0 {
+            compatible = "usb-c-connector";
+            reg = <0>;
+            power-role = "dual";
+            data-role = "dual";
+            try-power-role = "source";
+          };
+        };
+      };
+    };