From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops 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 --- net/x25/Kconfig | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 net/x25/Kconfig (limited to 'net/x25/Kconfig') diff --git a/net/x25/Kconfig b/net/x25/Kconfig new file mode 100644 index 000000000..dc72302cb --- /dev/null +++ b/net/x25/Kconfig @@ -0,0 +1,32 @@ +# SPDX-License-Identifier: GPL-2.0-only +# +# CCITT X.25 Packet Layer +# + +config X25 + tristate "CCITT X.25 Packet Layer" + help + X.25 is a set of standardized network protocols, similar in scope to + frame relay; the one physical line from your box to the X.25 network + entry point can carry several logical point-to-point connections + (called "virtual circuits") to other computers connected to the X.25 + network. Governments, banks, and other organizations tend to use it + to connect to each other or to form Wide Area Networks (WANs). Many + countries have public X.25 networks. X.25 consists of two + protocols: the higher level Packet Layer Protocol (PLP) (say Y here + if you want that) and the lower level data link layer protocol LAPB + (say Y to "LAPB Data Link Driver" below if you want that). + + Information about X.25 for Linux is contained in the files + and + . + + One connects to an X.25 network either with a dedicated network card + using the X.21 protocol (not yet supported by Linux) or one can do + X.25 over a standard telephone line using an ordinary modem (say Y + to "X.25 async driver" below) or over Ethernet using an ordinary + Ethernet card and the LAPB over Ethernet (say Y to "LAPB Data Link + Driver" and "LAPB over Ethernet driver" below). + + To compile this driver as a module, choose M here: the module + will be called x25. If unsure, say N. -- cgit v1.3.1