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, 21 insertions, 0 deletions

diff --git a/drivers/nvme/common/Kconfig b/drivers/nvme/common/Kconfig
new file mode 100644
index 000000000..f1639db65
--- /dev/null
+++ b/drivers/nvme/common/Kconfig
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config NVME_KEYRING
+       tristate
+       select KEYS
+
+config NVME_AUTH
+	tristate
+	select CRYPTO
+	select CRYPTO_DH
+	select CRYPTO_DH_RFC7919_GROUPS
+	select CRYPTO_LIB_SHA256
+	select CRYPTO_LIB_SHA512
+
+config NVME_AUTH_KUNIT_TEST
+	tristate "KUnit tests for NVMe authentication" if !KUNIT_ALL_TESTS
+	depends on KUNIT && NVME_AUTH
+	default KUNIT_ALL_TESTS
+	help
+	  Enable KUnit tests for some of the common code for NVMe over Fabrics
+	  In-Band Authentication.