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, 48 insertions, 0 deletions

diff --git a/drivers/phy/cadence/Kconfig b/drivers/phy/cadence/Kconfig
new file mode 100644
index 000000000..1adde2d99
--- /dev/null
+++ b/drivers/phy/cadence/Kconfig
@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Phy drivers for Cadence PHYs
+#
+
+config PHY_CADENCE_TORRENT
+	tristate "Cadence Torrent PHY driver"
+	depends on OF
+	depends on HAS_IOMEM
+	depends on COMMON_CLK
+	select GENERIC_PHY
+	help
+	  Support for Cadence Torrent PHY.
+
+config PHY_CADENCE_DPHY
+	tristate "Cadence D-PHY Support"
+	depends on HAS_IOMEM && OF
+	select GENERIC_PHY
+	select GENERIC_PHY_MIPI_DPHY
+	help
+	  Choose this option if you have a Cadence D-PHY in your
+	  system. If M is selected, the module will be called
+	  cdns-dphy.
+
+config PHY_CADENCE_DPHY_RX
+	tristate "Cadence D-PHY Rx Support"
+	depends on HAS_IOMEM && OF
+	select GENERIC_PHY
+	select GENERIC_PHY_MIPI_DPHY
+	help
+	  Support for Cadence D-PHY in Rx configuration.
+
+config PHY_CADENCE_SIERRA
+	tristate "Cadence Sierra PHY Driver"
+	depends on OF && HAS_IOMEM && RESET_CONTROLLER
+	depends on COMMON_CLK
+	select GENERIC_PHY
+	help
+	  Enable this to support the Cadence Sierra PHY driver
+
+config PHY_CADENCE_SALVO
+	tristate "Cadence Salvo PHY Driver"
+	depends on OF && HAS_IOMEM
+	select GENERIC_PHY
+	help
+	  Enable this to support the Cadence SALVO PHY driver,
+	  this PHY is a legacy PHY, and only are used for USB3
+	  and USB2.