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 --- tools/perf/util/build-id.h | 79 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 tools/perf/util/build-id.h (limited to 'tools/perf/util/build-id.h') diff --git a/tools/perf/util/build-id.h b/tools/perf/util/build-id.h new file mode 100644 index 000000000..73bad90b0 --- /dev/null +++ b/tools/perf/util/build-id.h @@ -0,0 +1,79 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef PERF_BUILD_ID_H_ +#define PERF_BUILD_ID_H_ 1 + +#define BUILD_ID_SIZE 20 /* SHA-1 length in bytes */ +#define BUILD_ID_MIN_SIZE 16 /* MD5/UUID/GUID length in bytes */ +#define SBUILD_ID_SIZE (BUILD_ID_SIZE * 2 + 1) +#define SBUILD_ID_MIN_SIZE (BUILD_ID_MIN_SIZE * 2 + 1) + +#include "machine.h" +#include "tool.h" +#include + +struct build_id { + u8 data[BUILD_ID_SIZE]; + u8 size; +}; + +struct dso; +struct feat_fd; +struct nsinfo; + +void build_id__init(struct build_id *bid, const u8 *data, size_t size); +int build_id__snprintf(const struct build_id *build_id, char *bf, size_t bf_size); +bool build_id__is_defined(const struct build_id *bid); +int sysfs__snprintf_build_id(const char *root_dir, char *sbuild_id, size_t sbuild_id_size); +int filename__snprintf_build_id(const char *pathname, char *sbuild_id, size_t sbuild_id_size); +char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf, + size_t size); + +char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size, + bool is_debug); +char *__dso__build_id_filename(const struct dso *dso, char *bf, size_t size, + bool is_debug, bool is_kallsyms); + +int build_id__mark_dso_hit(const struct perf_tool *tool, union perf_event *event, + struct perf_sample *sample, struct machine *machine); + +bool perf_session__read_build_ids(struct perf_session *session, bool with_hits); +int perf_session__write_buildid_table(struct perf_session *session, + struct feat_fd *fd); +int perf_session__cache_build_ids(struct perf_session *session); +int __perf_session__cache_build_ids(struct perf_session *session, + machine__dso_t fn, void *priv); + +char *build_id_cache__origname(const char *sbuild_id); +char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size); +char *build_id_cache__cachedir(const char *sbuild_id, const char *name, + struct nsinfo *nsi, bool is_kallsyms, + bool is_vdso); + +struct strlist; + +struct strlist *build_id_cache__list_all(bool validonly); +char *build_id_cache__complement(const char *incomplete_sbuild_id); +int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi, + struct strlist **result); +bool build_id_cache__cached(const char *sbuild_id); +int build_id_cache__add(const char *sbuild_id, const char *name, const char *realname, + struct nsinfo *nsi, bool is_kallsyms, bool is_vdso, + const char *proper_name, const char *root_dir); +int __build_id_cache__add_s(const char *sbuild_id, + const char *name, struct nsinfo *nsi, + bool is_kallsyms, bool is_vdso, + const char *proper_name, const char *root_dir); +static inline int build_id_cache__add_s(const char *sbuild_id, + const char *name, struct nsinfo *nsi, + bool is_kallsyms, bool is_vdso) +{ + return __build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms, is_vdso, NULL, NULL); +} +int build_id_cache__remove_s(const char *sbuild_id); + +extern char buildid_dir[]; + +void set_buildid_dir(const char *dir); +void disable_buildid_cache(void); + +#endif -- cgit v1.3.1