Hi, Here is the 4th version of the series to use ftrace_regs instead of pt_regs in fprobe. The previous version is here; https://lore.kernel.org/all/169181859570.505132.10136520092011157898.stgit@devnote2/ This version fixes the issues pointed in the previous series; fix document description, keep CONFIG_FPROBE dependency for multi-kprobe, add static_assert check for ftrace_regs size, reorder the ftrace_partial_regs() patch for perf fprobe event support, introduce per-cpu pt_regs stack for perf fprobe event and add Florent's Ack (Thanks!). Also this adds a new documentation patch to clarify that the $argN and $retval is best effort. - Document fix for the current fprobe callback prototype - Simply replace pt_regs in fprobe_entry_handler with ftrace_regs. - Expose ftrace_regs even if CONFIG_FUNCTION_TRACER=n. - Introduce ftrace_partial_regs(). (This changes ARM64 which needs a custom implementation) - Replace pt_regs in rethook and fprobe_exit_handler with ftrace_regs. This introduce a new HAVE_PT_REGS_TO_FTRACE_REGS_CAST which means ftrace_regs is just a wrapper of pt_regs (except for arm64, other architectures do this) - Update fprobe-events to use ftrace_regs natively. - Update bpf multi-kprobe handler use ftrace_partial_regs(). - Update document for new fprobe callbacks. - Add notes for the $argN and $retval. This series can be applied against the probes/core branch on linux-trace tree. This series can also be found below branch. https://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux.git/log/?h=topic/fprobe-ftrace-regs Thank you, --- Masami Hiramatsu (Google) (9): Documentation: probes: Add a new ret_ip callback parameter fprobe: Use fprobe_regs in fprobe entry handler tracing: Expose ftrace_regs regardless of CONFIG_FUNCTION_TRACER fprobe: rethook: Use ftrace_regs in fprobe exit handler and rethook ftrace: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled Documentations: probes: Update fprobe document to use ftrace_regs Documentation: tracing: Add a note about argument and retval access Documentation/trace/fprobe.rst | 18 +++-- Documentation/trace/fprobetrace.rst | 8 ++ Documentation/trace/kprobetrace.rst | 8 ++ arch/Kconfig | 1 arch/arm64/include/asm/ftrace.h | 11 +++ arch/loongarch/Kconfig | 1 arch/s390/Kconfig | 1 arch/s390/include/asm/ftrace.h | 4 + arch/x86/Kconfig | 1 arch/x86/kernel/rethook.c | 13 ++- include/linux/fprobe.h | 4 + include/linux/ftrace.h | 89 ++++++++++++++++++------ include/linux/rethook.h | 11 ++- kernel/kprobes.c | 10 ++- kernel/trace/Kconfig | 9 ++ kernel/trace/bpf_trace.c | 14 ++-- kernel/trace/fprobe.c | 10 +-- kernel/trace/rethook.c | 16 ++-- kernel/trace/trace_fprobe.c | 131 ++++++++++++++++++++++++++--------- kernel/trace/trace_probe_tmpl.h | 2 - lib/test_fprobe.c | 10 +-- samples/fprobe/fprobe_example.c | 4 + 22 files changed, 267 insertions(+), 109 deletions(-) -- Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>