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/libbfd.h | 82 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 tools/perf/util/libbfd.h (limited to 'tools/perf/util/libbfd.h') diff --git a/tools/perf/util/libbfd.h b/tools/perf/util/libbfd.h new file mode 100644 index 000000000..953886f3d --- /dev/null +++ b/tools/perf/util/libbfd.h @@ -0,0 +1,82 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __PERF_LIBBFD_H +#define __PERF_LIBBFD_H + +#include +#include +#include +#include + +struct annotate_args; +struct build_id; +struct dso; +struct inline_node; +struct symbol; + +#ifdef HAVE_LIBBFD_SUPPORT +int libbfd__addr2line(const char *dso_name, u64 addr, + char **file, unsigned int *line, struct dso *dso, + bool unwind_inlines, struct inline_node *node, + struct symbol *sym); + + +void dso__free_a2l_libbfd(struct dso *dso); + +int symbol__disassemble_libbfd(const char *filename, struct symbol *sym, + struct annotate_args *args); + +int libbfd__read_build_id(const char *filename, struct build_id *bid); + +int libbfd_filename__read_debuglink(const char *filename, char *debuglink, size_t size); + +int symbol__disassemble_bpf_libbfd(struct symbol *sym, struct annotate_args *args); + +#else // !defined(HAVE_LIBBFD_SUPPORT) +#include "annotate.h" + +static inline int libbfd__addr2line(const char *dso_name __always_unused, + u64 addr __always_unused, + char **file __always_unused, + unsigned int *line __always_unused, + struct dso *dso __always_unused, + bool unwind_inlines __always_unused, + struct inline_node *node __always_unused, + struct symbol *sym __always_unused) +{ + return -1; +} + + +static inline void dso__free_a2l_libbfd(struct dso *dso __always_unused) +{ +} + +static inline int symbol__disassemble_libbfd(const char *filename __always_unused, + struct symbol *sym __always_unused, + struct annotate_args *args __always_unused) +{ + return -1; +} + +static inline int libbfd__read_build_id(const char *filename __always_unused, + struct build_id *bid __always_unused) +{ + return -1; +} + +static inline int libbfd_filename__read_debuglink(const char *filename __always_unused, + char *debuglink __always_unused, + size_t size __always_unused) +{ + return -1; +} + +static inline int symbol__disassemble_bpf_libbfd(struct symbol *sym __always_unused, + struct annotate_args *args __always_unused) +{ + return SYMBOL_ANNOTATE_ERRNO__NO_LIBOPCODES_FOR_BPF; +} + +#endif // defined(HAVE_LIBBFD_SUPPORT) + +#endif /* __PERF_LIBBFD_H */ -- cgit v1.3.1