[PATCH -tip v2 00/10] kprobes: Fix stacktrace with kretprobes

From: Masami Hiramatsu
Date: Fri Mar 12 2021 - 01:42:28 EST


Hello,

Here is the 2nd version of the series to fix the stacktrace with kretprobe.

The 1st series is here;

https://lore.kernel.org/bpf/161495873696.346821.10161501768906432924.stgit@devnote2/

In this version I merged the ORC unwinder fix for kretprobe which discussed in the
previous thread. [3/10] is updated according to the Miroslav's comment. [4/10] is
updated for simplify the code. [5/10]-[9/10] are discussed in the previsous tread
and are introduced to the series.

Daniel, can you also test this again? I and Josh discussed a bit different
method and I've implemented it on this version.

This actually changes the kretprobe behavisor a bit, now the instraction pointer in
the pt_regs passed to kretprobe user handler is correctly set the real return
address. So user handlers can get it via instruction_pointer() API.

Thank you,

---

Josh Poimboeuf (1):
x86/kprobes: Add UNWIND_HINT_FUNC on kretprobe_trampoline code

Masami Hiramatsu (9):
ia64: kprobes: Fix to pass correct trampoline address to the handler
kprobes: treewide: Replace arch_deref_entry_point() with dereference_function_descriptor()
kprobes: treewide: Remove trampoline_address from kretprobe_trampoline_handler()
kprobes: stacktrace: Recover the address changed by kretprobe
ARC: Add instruction_pointer_set() API
ia64: Add instruction_pointer_set() API
kprobes: Setup instruction pointer in __kretprobe_trampoline_handler
x86/unwind/orc: Fixup kretprobe trampoline entry
tracing: Remove kretprobe unknown indicator from stacktrace


arch/arc/include/asm/ptrace.h | 5 ++
arch/arc/kernel/kprobes.c | 2 -
arch/arm/probes/kprobes/core.c | 3 -
arch/arm64/kernel/probes/kprobes.c | 3 -
arch/csky/kernel/probes/kprobes.c | 2 -
arch/ia64/include/asm/ptrace.h | 6 +++
arch/ia64/kernel/kprobes.c | 15 ++----
arch/mips/kernel/kprobes.c | 3 -
arch/parisc/kernel/kprobes.c | 4 +-
arch/powerpc/kernel/kprobes.c | 13 -----
arch/riscv/kernel/probes/kprobes.c | 2 -
arch/s390/kernel/kprobes.c | 2 -
arch/sh/kernel/kprobes.c | 2 -
arch/sparc/kernel/kprobes.c | 2 -
arch/x86/include/asm/unwind.h | 4 ++
arch/x86/include/asm/unwind_hints.h | 5 ++
arch/x86/kernel/kprobes/core.c | 5 +-
arch/x86/kernel/unwind_orc.c | 16 +++++++
include/linux/kprobes.h | 41 +++++++++++++++--
kernel/kprobes.c | 84 +++++++++++++++++++++--------------
kernel/stacktrace.c | 22 +++++++++
kernel/trace/trace_output.c | 27 ++---------
lib/error-inject.c | 3 +
23 files changed, 170 insertions(+), 101 deletions(-)

--
Masami Hiramatsu (Linaro) <mhiramat@xxxxxxxxxx>