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, 59 insertions, 0 deletions

diff --git a/fs/ntfs/Kconfig b/fs/ntfs/Kconfig
new file mode 100644
index 000000000..f88f4138f
--- /dev/null
+++ b/fs/ntfs/Kconfig
@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config NTFS_FS
+	tristate "NTFS file system support"
+	select NLS
+	select FS_IOMAP
+	help
+	  NTFS is the file system of Microsoft Windows NT, 2000, XP and 2003.
+	  This allows you to mount devices formatted with the ntfs file system.
+
+	  To compile this as a module, choose M here: the module will be called
+	  ntfs.
+
+config NTFS_FS_WOF_COMPRESSION
+	bool "NTFS Windows system compression support"
+	depends on NTFS_FS
+	help
+	  Enable read support for Windows system-compressed files.
+	  Windows more aggressively compresses system files such as binaries
+	  and DLLs using system compression. It is optimized for files that
+	  are rarely modified.
+	  Enabling this option builds the decompression support into the NTFS
+	  module.
+
+config NTFS_DEBUG
+	bool "NTFS debugging support"
+	depends on NTFS_FS
+	help
+	  If you are experiencing any problems with the NTFS file system, say
+	  Y here.  This will result in additional consistency checks to be
+	  performed by the driver as well as additional debugging messages to
+	  be written to the system log.  Note that debugging messages are
+	  disabled by default.  To enable them, supply the option debug_msgs=1
+	  at the kernel command line when booting the kernel or as an option
+	  to insmod when loading the ntfs module.  Once the driver is active,
+	  you can enable debugging messages by doing (as root):
+	  echo 1 > /proc/sys/fs/ntfs-debug
+	  Replacing the "1" with "0" would disable debug messages.
+
+	  If you leave debugging messages disabled, this results in little
+	  overhead, but enabling debug messages results in very significant
+	  slowdown of the system.
+
+	  When reporting bugs, please try to have available a full dump of
+	  debugging messages while the misbehaviour was occurring.
+
+config NTFS_FS_POSIX_ACL
+	bool "NTFS POSIX Access Control Lists"
+	depends on NTFS_FS
+	select FS_POSIX_ACL
+	help
+	  POSIX Access Control Lists (ACLs) support additional access rights
+	  for users and groups beyond the standard owner/group/world scheme.
+
+	  This option enables ACL support for ntfs, providing functional parity
+	  with ntfs3 drivier.
+
+	  NOTE: this is linux only feature. Windows will ignore these ACLs.
+
+	  If you don't know what Access Control Lists are, say N.