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, 23 insertions, 0 deletions

diff --git a/drivers/net/ipa/Kconfig b/drivers/net/ipa/Kconfig
new file mode 100644
index 000000000..a9aff1b79
--- /dev/null
+++ b/drivers/net/ipa/Kconfig
@@ -0,0 +1,23 @@
+config QCOM_IPA
+	tristate "Qualcomm IPA support"
+	depends on NET && QCOM_SMEM
+	depends on ARCH_QCOM || COMPILE_TEST
+	depends on INTERCONNECT
+	depends on QCOM_RPROC_COMMON || (QCOM_RPROC_COMMON=n && COMPILE_TEST)
+	depends on QCOM_AOSS_QMP || QCOM_AOSS_QMP=n
+	select QCOM_MDT_LOADER
+	select QCOM_PAS
+	select QCOM_QMI_HELPERS
+	help
+	  Choose Y or M here to include support for the Qualcomm
+	  IP Accelerator (IPA), a hardware block present in some
+	  Qualcomm SoCs.  The IPA is a programmable protocol processor
+	  that is capable of generic hardware handling of IP packets,
+	  including routing, filtering, and NAT.  Currently the IPA
+	  driver supports only basic transport of network traffic
+	  between the AP and modem.
+
+	  Note that if selected, the selection type must match that
+	  of QCOM_Q6V5_COMMON (Y or M).
+
+	  If unsure, say N.