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, 135 insertions, 0 deletions

diff --git a/scripts/sbom/sbom.py b/scripts/sbom/sbom.py
new file mode 100644
index 000000000..764175b9c
--- /dev/null
+++ b/scripts/sbom/sbom.py
@@ -0,0 +1,135 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0-only OR MIT
+# Copyright (C) 2025 TNG Technology Consulting GmbH
+
+"""
+Compute software bill of materials in SPDX format describing a kernel build.
+"""
+
+import json
+import logging
+import os
+import sys
+import time
+import uuid
+import sbom.sbom_logging as sbom_logging
+from sbom.config import get_config
+from sbom.path_utils import is_relative_to
+from sbom.spdx import JsonLdSpdxDocument, SpdxIdGenerator
+from sbom.spdx.core import CreationInfo, SpdxDocument
+from sbom.spdx_graph import SpdxIdGeneratorCollection, build_spdx_graphs
+from sbom.cmd_graph import CmdGraph
+
+
+def _exit_with_summary(write_output_on_error: bool = False) -> None:
+    warning_summary = sbom_logging.summarize_warnings()
+    error_summary = sbom_logging.summarize_errors()
+    if warning_summary:
+        logging.warning(warning_summary)
+    if error_summary:
+        logging.error(error_summary)
+        if not write_output_on_error:
+            logging.info(
+                "Use --write-output-on-error to generate output documents even when errors occur. "
+                "Note that in this case the generated documents may be incomplete."
+            )
+        sys.exit(1)
+
+
+def main():
+    # Read config
+    config = get_config()
+
+    # Configure logging
+    logging.basicConfig(
+        level=logging.DEBUG if config.debug else logging.INFO,
+        format="[%(levelname)s] %(message)s",
+    )
+
+    # Build cmd graph
+    logging.debug("Start building cmd graph")
+    start_time = time.time()
+    cmd_graph = CmdGraph.create(config.root_paths, config)
+    logging.debug(f"Built cmd graph in {time.time() - start_time} seconds")
+
+    # Save used files document
+    if config.generate_used_files:
+        if config.src_tree == config.obj_tree:
+            logging.info(
+                f"Extracting all files from the cmd graph to {config.used_files_file_name} "
+                "instead of only source files because source files cannot be "
+                "reliably classified when the source and object trees are identical.",
+            )
+            used_files = [os.path.relpath(node.absolute_path, config.src_tree) for node in cmd_graph]
+            logging.debug(f"Found {len(used_files)} files in cmd graph.")
+        else:
+            used_files = [
+                os.path.relpath(node.absolute_path, config.src_tree)
+                for node in cmd_graph
+                if is_relative_to(node.absolute_path, config.src_tree)
+                and not is_relative_to(node.absolute_path, config.obj_tree)
+            ]
+            logging.debug(f"Found {len(used_files)} source files in cmd graph")
+        if not sbom_logging.has_errors() or config.write_output_on_error:
+            used_files_path = os.path.join(config.output_directory, config.used_files_file_name)
+            with open(used_files_path, "w", encoding="utf-8") as f:
+                f.write("\n".join(str(file_path) for file_path in used_files))
+            logging.debug(f"Successfully saved {used_files_path}")
+
+    if config.generate_spdx is False:
+        _exit_with_summary(config.write_output_on_error)
+        return
+
+    # Build SPDX Documents
+    logging.debug("Start generating SPDX graph based on cmd graph")
+    start_time = time.time()
+
+    # The real uuid will be generated based on the content of the SPDX graphs
+    # to ensure that the same SPDX document is always assigned the same uuid.
+    PLACEHOLDER_UUID = "00000000-0000-0000-0000-000000000000"
+    spdx_id_base_namespace = f"{config.spdxId_prefix}{PLACEHOLDER_UUID}/"
+    spdx_id_generators = SpdxIdGeneratorCollection(
+        base=SpdxIdGenerator(prefix="p", namespace=spdx_id_base_namespace),
+        source=SpdxIdGenerator(prefix="s", namespace=f"{spdx_id_base_namespace}source/"),
+        build=SpdxIdGenerator(prefix="b", namespace=f"{spdx_id_base_namespace}build/"),
+        output=SpdxIdGenerator(prefix="o", namespace=f"{spdx_id_base_namespace}output/"),
+    )
+
+    spdx_graphs = build_spdx_graphs(
+        cmd_graph,
+        spdx_id_generators,
+        config,
+    )
+    spdx_id_uuid = uuid.uuid5(
+        uuid.NAMESPACE_URL,
+        "".join(
+            json.dumps(element.to_dict()) for spdx_graph in spdx_graphs.values() for element in spdx_graph.to_list()
+        ),
+    )
+    logging.debug(f"Generated SPDX graph in {time.time() - start_time} seconds")
+
+    if not sbom_logging.has_errors() or config.write_output_on_error:
+        for kernel_sbom_kind, spdx_graph in spdx_graphs.items():
+            spdx_graph_objects = spdx_graph.to_list()
+            # Add warning and error summary to creation info comment
+            creation_info = next(element for element in spdx_graph_objects if isinstance(element, CreationInfo))
+            creation_info.comment = "\n".join([
+                sbom_logging.summarize_warnings(),
+                sbom_logging.summarize_errors(),
+            ]).strip()
+            # Replace Placeholder uuid with real uuid for spdxIds
+            spdx_document = next(element for element in spdx_graph_objects if isinstance(element, SpdxDocument))
+            for namespaceMap in spdx_document.namespaceMap:
+                namespaceMap.namespace = namespaceMap.namespace.replace(PLACEHOLDER_UUID, str(spdx_id_uuid))
+            # Serialize SPDX graph to JSON-LD
+            spdx_doc = JsonLdSpdxDocument(graph=spdx_graph_objects)
+            save_path = os.path.join(config.output_directory, config.spdx_file_names[kernel_sbom_kind])
+            spdx_doc.save(save_path, config.prettify_json)
+            logging.debug(f"Successfully saved {save_path}")
+
+    _exit_with_summary(config.write_output_on_error)
+
+
+# Call main method
+if __name__ == "__main__":
+    main()