Hello,
Here is a series of patches for kprobes and stacktracer to fix the kretprobe
entries in the kernel stack. This was reported by Daniel Xu. I thought that
was in the bpftrace, but it is actually more generic issue.
So I decided to fix the issue in arch independent part.
While fixing the issue, I found a bug in ia64 related to kretprobe, which is
fixed by [1/5]. [2/5] and [3/5] is a kind of cleanup before fixing the main
issue. [4/5] is the patch to fix the stacktrace, which involves kretprobe
internal change. And [5/5] removing the stacktrace kretprobe fixup code in
ftrace.
Daniel, can you also check that this fixes your issue too? I hope it is.
Note that this doesn't fixup all cases. Unfortunately, stacktracing the
other tasks (non current task) on the arch which doesn't support ARCH_STACKWALK,
I can not fix it in the arch independent code. Maybe each arch dependent
stacktrace implementation must fixup by themselves.
Thank you,
---
Masami Hiramatsu (5):
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
tracing: Remove kretprobe unknown indicator from stacktrace
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/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/kernel/kprobes/core.c | 2 -
include/linux/kprobes.h | 32 +++++++++++--
kernel/kprobes.c | 89 ++++++++++++++++++++++--------------
kernel/stacktrace.c | 21 ++++++++
kernel/trace/trace_output.c | 27 ++---------
lib/error-inject.c | 3 +
18 files changed, 126 insertions(+), 101 deletions(-)
--
Masami Hiramatsu (Linaro) <mhiramat@xxxxxxxxxx>
