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 --- Documentation/sphinx/kernel_abi.py | 173 +++++++++++++++++++++++++++++++++++++ 1 file changed, 173 insertions(+) create mode 100644 Documentation/sphinx/kernel_abi.py (limited to 'Documentation/sphinx/kernel_abi.py') diff --git a/Documentation/sphinx/kernel_abi.py b/Documentation/sphinx/kernel_abi.py new file mode 100644 index 000000000..5667f207d --- /dev/null +++ b/Documentation/sphinx/kernel_abi.py @@ -0,0 +1,173 @@ +# -*- coding: utf-8; mode: python -*- +# coding=utf-8 +# SPDX-License-Identifier: GPL-2.0 +# +""" + kernel-abi + ~~~~~~~~~~ + + Implementation of the ``kernel-abi`` reST-directive. + + :copyright: Copyright (C) 2016 Markus Heiser + :copyright: Copyright (C) 2016-2020 Mauro Carvalho Chehab + :maintained-by: Mauro Carvalho Chehab + :license: GPL Version 2, June 1991 see Linux/COPYING for details. + + The ``kernel-abi`` (:py:class:`KernelCmd`) directive calls the + AbiParser class to parse the Kernel ABI files. + + Overview of directive's argument and options. + + .. code-block:: rst + + .. kernel-abi:: + :debug: + + The argument ```` is required. It contains the + location of the ABI files to be parsed. + + ``debug`` + Inserts a code-block with the *raw* reST. Sometimes it is helpful to see + what reST is generated. + +""" + +import os +import re +import sys + +from docutils import nodes, statemachine +from docutils.statemachine import ViewList +from docutils.parsers.rst import directives, Directive +from sphinx.util.docutils import switch_source_input +from sphinx.util import logging + +srctree = os.path.abspath(os.environ["srctree"]) +sys.path.insert(0, os.path.join(srctree, "tools/lib/python")) + +from abi.abi_parser import AbiParser + +__version__ = "1.0" + +logger = logging.getLogger('kernel_abi') +path = os.path.join(srctree, "Documentation/ABI") + +_kernel_abi = None + +def get_kernel_abi(): + """ + Initialize kernel_abi global var, if not initialized yet. + + This is needed to avoid warnings during Sphinx module initialization. + """ + global _kernel_abi + + if not _kernel_abi: + # Parse ABI symbols only once + _kernel_abi = AbiParser(path, logger=logger) + _kernel_abi.parse_abi() + _kernel_abi.check_issues() + + return _kernel_abi + +def setup(app): + + app.add_directive("kernel-abi", KernelCmd) + return { + "version": __version__, + "parallel_read_safe": True, + "parallel_write_safe": True + } + + +class KernelCmd(Directive): + """KernelABI (``kernel-abi``) directive""" + + required_arguments = 1 + optional_arguments = 3 + has_content = False + final_argument_whitespace = True + parser = None + + option_spec = { + "debug": directives.flag, + "no-symbols": directives.flag, + "no-files": directives.flag, + } + + def run(self): + kernel_abi = get_kernel_abi() + + doc = self.state.document + if not doc.settings.file_insertion_enabled: + raise self.warning("docutils: file insertion disabled") + + env = self.state.document.settings.env + content = ViewList() + node = nodes.section() + + abi_type = self.arguments[0] + + if "no-symbols" in self.options: + show_symbols = False + else: + show_symbols = True + + if "no-files" in self.options: + show_file = False + else: + show_file = True + + tab_width = self.options.get('tab-width', + self.state.document.settings.tab_width) + + old_f = None + n = 0 + n_sym = 0 + for msg, f, ln in kernel_abi.doc(show_file=show_file, + show_symbols=show_symbols, + filter_path=abi_type): + n_sym += 1 + msg_list = statemachine.string2lines(msg, tab_width, + convert_whitespace=True) + if "debug" in self.options: + lines = [ + "", "", ".. code-block:: rst", + " :linenos:", "" + ] + for m in msg_list: + lines.append(" " + m) + else: + lines = msg_list + + for line in lines: + # sphinx counts lines from 0 + content.append(line, f, ln - 1) + n += 1 + + if f != old_f: + # Add the file to Sphinx build dependencies if the file exists + fname = os.path.join(srctree, f) + if os.path.isfile(fname): + env.note_dependency(fname) + + old_f = f + + # Sphinx doesn't like to parse big messages. So, let's + # add content symbol by symbol + if content: + self.do_parse(content, node) + content = ViewList() + + if show_symbols and not show_file: + logger.verbose("%s ABI: %i symbols (%i ReST lines)" % (abi_type, n_sym, n)) + elif not show_symbols and show_file: + logger.verbose("%s ABI: %i files (%i ReST lines)" % (abi_type, n_sym, n)) + else: + logger.verbose("%s ABI: %i data (%i ReST lines)" % (abi_type, n_sym, n)) + + return node.children + + def do_parse(self, content, node): + with switch_source_input(self.state, content): + self.state.nested_parse(content, 0, node, match_titles=1) -- cgit v1.3.1